Manifold API

Programatic access to Manifold.

caution

Our API is still in alpha — things may change or break at any time!

If you have questions, come chat with us on Discord. We’d love to hear about what you build!

General notes

Some APIs are not associated with any particular user. Other APIs require authentication.

APIs that require authentication accept an Authorization header in one of two formats:

Authorization: Key {key}. A Manifold API key associated with a user account. Each account may have zero or one API keys. To generate an API key for your account, visit your user profile, click "edit", and click the "refresh" button next to the API key field at the bottom. You can click it again any time to invalidate your existing key and generate a new one.
Authorization: Bearer {jwt}. A signed JWT from Firebase asserting your identity. This is what our web client uses. It will probably be annoying for you to generate and we will not document it further here.

API requests that accept parameters should either have the parameters in the query string if they are GET requests, or have a body with a JSON object with one property per parameter if they are POST requests.

API responses should always either have a body with a JSON result object (if the response was a 200) or with a JSON object representing an error (if the response was a 4xx or 5xx.)

Usage Guidelines

Feel free to use the API for any purpose you'd like. We ask that you:

Keep your bets to less than 10 per minute, amortized (transient spikes of over 10/min are okay).
Keep your reads to less than 100 per second.

Fees

A non-refundable transaction fee of M0.25 will be levied on any bet, sell, or limit order placed through the API, or by any account marked as a bot.
Comments placed through the API will incur a M1 transaction fee.

Trade history dumps

For data analysis and backtesting purposes, you can bulk download all markets and bets/trades on the platform.

Markets dump (10MB)
Bets dump (436MB)

Last updated: August 8th, 2023

Endpoints

`GET /v0/user/[username]`

Gets a user by their username. Remember that usernames may change.

Requires no authorization.

`GET /v0/user/by-id/[id]`

Gets a user by their unique ID. Many other API endpoints return this as the userId.

Requires no authorization.

`GET /v0/me`

Returns the authenticated user.

`GET /v0/groups`

Gets all groups, in no particular order.

Parameters:

availableToUserId: Optional. if specified, only groups that the user can join and groups they've already joined will be returned.

Requires no authorization.

`GET /v0/group/[slug]`

Gets a group by its slug.

Requires no authorization. Note: group is singular in the URL.

`GET /v0/group/by-id/[id]`

Gets a group by its unique ID.

Requires no authorization. Note: group is singular in the URL.

`GET /v0/group/by-id/[id]/markets`

Gets a group's markets by its unique ID.

Requires no authorization. Note: group is singular in the URL.

`GET /v0/markets`

Lists all markets, ordered by creation date descending.

Parameters:

limit: Optional. How many markets to return. The maximum is 1000 and the default is 500.
before: Optional. The ID of the market before which the list will start. For example, if you ask for the most recent 10 markets, and then perform a second query for 10 more markets with before=[the id of the 10th market], you will get markets 11 through 20.

Requires no authorization.

Example request

https://manifold.markets/api/v0/markets?limit=1

Example response

[
  {
    "id":"EvIhzcJXwhL0HavaszD7",
    "creatorUsername":"Austin",
    "creatorName":"Austin",
    "createdTime":1653850472294,
    "creatorAvatarUrl":"https://lh3.googleusercontent.com/a-/AOh14GiZyl1lBehuBMGyJYJhZd-N-mstaUtgE4xdI22lLw=s96-c",
    "closeTime":1653893940000,
    "question":"Will I write a new blog post today?",
    "url":"https://manifold.markets/Austin/will-i-write-a-new-blog-post-today",
    "pool":146.73022894879944,
    "probability":0.8958175225896258,
    "p":0.08281474972181882,
    "totalLiquidity":102.65696071594805,
    "outcomeType":"BINARY",
    "mechanism":"cpmm-1",
    "volume":241,
    "volume24Hours":0,
    "isResolved":true,
    "resolution":"YES",
    "resolutionTime":1653924077078
  },
  ...

Response type: Array of LiteMarket

// Information about a market, but without bets or comments
type LiteMarket = {
  // Unique identifer for this market
  id: string

  // Attributes about the creator
  creatorUsername: string
  creatorName: string
  createdTime: number // milliseconds since epoch
  creatorAvatarUrl?: string

  // Market attributes. All times are in milliseconds since epoch
  closeTime?: number // Min of creator's chosen date, and resolutionTime
  question: string

  // Note: This url always points to https://manifold.markets, regardless of what instance the api is running on.
  // This url includes the creator's username, but this doesn't need to be correct when constructing valid URLs.
  //   i.e. https://manifold.markets/Austin/test-market is the same as https://manifold.markets/foo/test-market
  url: string

  outcomeType: string // BINARY, FREE_RESPONSE, MULTIPLE_CHOICE, NUMERIC, or PSEUDO_NUMERIC
  mechanism: string // dpm-2 or cpmm-1

  probability: number
  pool: { outcome: number } // For CPMM markets, the number of shares in the liquidity pool. For DPM markets, the amount of mana invested in each answer.
  p?: number // CPMM markets only, probability constant in y^p * n^(1-p) = k
  totalLiquidity?: number // CPMM markets only, the amount of mana deposited into the liquidity pool
  value?: number // PSEUDO_NUMERIC markets only, the current market value, which is mapped from probability using min, max, and isLogScale.
  min?: number // PSEUDO_NUMERIC markets only, the minimum resolvable value
  max?: number // PSEUDO_NUMERIC markets only, the maximum resolvable value
  isLogScale?: bool // PSEUDO_NUMERIC markets only, if true `number = (max - min + 1)^probability + minstart - 1`, otherwise `number = min + (max - min) * probability`

  volume: number
  volume24Hours: number

  isResolved: boolean
  resolutionTime?: number
  resolution?: string
  resolutionProbability?: number // Used for BINARY markets resolved to MKT

  lastUpdatedTime?: number
}

`GET /v0/market/[marketId]`

Gets information about a single market by ID. Includes answers, but not bets and comments. Use /bets or /comments with a market ID to retrieve bets or comments.

Requires no authorization.

Example request

https://manifold.markets/api/v0/market/3zspH9sSzMlbFQLn9GKR

Example response

{
  "id": "lEoqtnDgJzft6apSKzYK",
  "creatorUsername": "Angela",
  "creatorName": "Angela",
  "createdTime": 1655258914863,
  "creatorAvatarUrl": "https://firebasestorage.googleapis.com/v0/b/mantic-markets.appspot.com/o/user-images%2FAngela%2F50463444807_edfd4598d6_o.jpeg?alt=media&token=ef44e13b-2e6c-4498-b9c4-8e38bdaf1476",
  "closeTime": 1655265001448,
  "question": "What is good?",
  "description": "Resolves proportionally to the answer(s) which I find most compelling. (Obviously I’ll refrain from giving my own answers)\n\n(Please have at it with philosophy, ethics, etc etc)\n\n\nContract resolved automatically.",
  "url": "https://manifold.markets/Angela/what-is-good",
  "pool": null,
  "outcomeType": "FREE_RESPONSE",
  "mechanism": "dpm-2",
  "volume": 112,
  "volume24Hours": 0,
  "isResolved": true,
  "resolution": "MKT",
  "resolutionTime": 1655265001448,
  "answers": [
    {
      "createdTime": 1655258941573,
      "avatarUrl": "https://firebasestorage.googleapis.com/v0/b/mantic-markets.appspot.com/o/user-images%2FAngela%2F50463444807_edfd4598d6_o.jpeg?alt=media&token=ef44e13b-2e6c-4498-b9c4-8e38bdaf1476",
      "id": "1",
      "username": "Angela",
      "number": 1,
      "name": "Angela",
      "contractId": "lEoqtnDgJzft6apSKzYK",
      "text": "ANTE",
      "userId": "qe2QqIlOkeWsbljfeF3MsxpSJ9i2",
      "probability": 0.66749733001068
    },
    {
      "name": "Isaac King",
      "username": "IsaacKing",
      "text": "This answer",
      "userId": "y1hb6k7txdZPV5mgyxPFApZ7nQl2",
      "id": "2",
      "number": 2,
      "avatarUrl": "https://lh3.googleusercontent.com/a-/AOh14GhNVriOvxK2VUAmE-jvYZwC-XIymatzVirT0Bqb2g=s96-c",
      "contractId": "lEoqtnDgJzft6apSKzYK",
      "createdTime": 1655261198074,
      "probability": 0.008922214311142757
    },
    {
      "createdTime": 1655263226587,
      "userId": "jbgplxty4kUKIa1MmgZk22byJq03",
      "id": "3",
      "avatarUrl": "https://firebasestorage.googleapis.com/v0/b/mantic-markets.appspot.com/o/user-images%2FMartin%2Fgiphy.gif?alt=media&token=422ef610-553f-47e3-bf6f-c0c5cc16c70a",
      "text": "Toyota Camry",
      "contractId": "lEoqtnDgJzft6apSKzYK",
      "name": "Undox",
      "username": "Undox",
      "number": 3,
      "probability": 0.008966714133143469
    },
    {
      "number": 4,
      "name": "James Grugett",
      "userId": "5LZ4LgYuySdL1huCWe7bti02ghx2",
      "text": "Utility (Defined by your personal utility function.)",
      "createdTime": 1655264793224,
      "contractId": "lEoqtnDgJzft6apSKzYK",
      "username": "JamesGrugett",
      "id": "4",
      "avatarUrl": "https://lh3.googleusercontent.com/a-/AOh14GjC83uMe-fEfzd6QvxiK6ZqZdlMytuHxevgMYIkpAI=s96-c",
      "probability": 0.09211463154147384
    }
  ]
}

Response type: A FullMarket

// A complete market, along with answers (for free response markets)
type FullMarket = LiteMarket & {
  answers?: Answer[] // dpm-2 markets only
  description: JSONContent // Rich text content. See https://tiptap.dev/guide/output#option-1-json
  textDescription: string // string description without formatting, images, or embeds
  groupSlugs?: string[] // groups which the market is a part of
}

`GET /v0/market/[marketId]/positions`

Get positions information about a single market by ID.

Parameters:

order - Optional. The field to order results by. Default: profit. Options: shares or profit,
top - Optional. The number of top positions (ordered by order) to return. Default: null.
bottom - Optional. The number of bottom positions (ordered by order) to return. Default: null.
userId - Optional. The user ID to query by. Default: null. If provided, only the position for this user will be returned.

Requires no authorization.

Example request

https://manifold.markets/api/v0/market/kupKInoLsjMuiDiNfogm/positions?top=1&bottom=1

Example response

[
  {
    "from": {
      "day": {
        "value": 23.479030029570662,
        "profit": 0,
        "invested": 23.479030029570662,
        "prevValue": 23.479030029570662,
        "profitPercent": 0
      },
      "week": {
        "value": 0,
        "profit": 8.479030029570673,
        "invested": 15,
        "prevValue": 0,
        "profitPercent": 56.52686686380448
      },
      "month": {
        "value": 0,
        "profit": 8.479030029570673,
        "invested": 15,
        "prevValue": 0,
        "profitPercent": 56.52686686380448
      }
    },
    "loan": 1.7123642870400002,
    "payout": 23.479030029570673,
    "profit": 8.479030029570673,
    "userId": "IpTiwOTs96VIzeoxu66tfitUcBZ2",
    "invested": 15,
    "userName": "Lucas Goldfein",
    "hasShares": true,
    "contractId": "kupKInoLsjMuiDiNfogm",
    "hasNoShares": true,
    "lastBetTime": 1678924706057,
    "totalShares": {
      "NO": 89.17418492518308
    },
    "hasYesShares": false,
    "userUsername": "LucasGoldfein56b1",
    "profitPercent": 56.52686686380448,
    "userAvatarUrl": "https://lh3.googleusercontent.com/a/AEdFTp5e7cFzq1moc91CKqaAgyEleoNTjtEL9ke8emzV=s96-c",
    "maxSharesOutcome": "NO"
  },
  {
    "from": {
      "day": {
        "value": 5.008090894597479,
        "profit": 0,
        "invested": 5.008090894597479,
        "prevValue": 5.008090894597479,
        "profitPercent": 0
      },
      "week": {
        "value": 0,
        "profit": -4.991909105402519,
        "invested": 10,
        "prevValue": 0,
        "profitPercent": -49.919091054025195
      },
      "month": {
        "value": 0,
        "profit": -4.991909105402519,
        "invested": 10,
        "prevValue": 0,
        "profitPercent": -49.919091054025195
      }
    },
    "loan": 1.14157619136,
    "payout": 5.008090894597481,
    "profit": -4.991909105402519,
    "userId": "JNkmw38JICdw6ySJ9RgWK7WyBdE2",
    "invested": 10,
    "userName": "Sylvie",
    "hasShares": true,
    "contractId": "kupKInoLsjMuiDiNfogm",
    "hasNoShares": true,
    "lastBetTime": 1678914591730,
    "totalShares": {
      "NO": 19.020906016751987
    },
    "hasYesShares": false,
    "userUsername": "sylv",
    "profitPercent": -49.919091054025195,
    "userAvatarUrl": "https://lh3.googleusercontent.com/a/AATXAJyoOZtkrJBItDvRE0HvcRDn8txM-_v033jFIifZ=s96-c",
    "maxSharesOutcome": "NO"
  }
]

Response type: An array of ContractMetric

// A single position in a market
type ContractMetric = {
  contractId: string
  from:
    | {
        // includes, day, week,month
        [period: string]: {
          profit: number
          profitPercent: number
          invested: number
          prevValue: number
          value: number
        }
      }
    | undefined
  hasNoShares: boolean
  hasShares: boolean
  hasYesShares: boolean
  invested: number
  loan: number
  maxSharesOutcome: string | null
  payout: number
  profit: number
  profitPercent: number
  totalShares: {
    [outcome: string]: number
  }
  userId: string
  userUsername: string
  userName: string
  userAvatarUrl: string
  lastBetTime: number
}

`GET /v0/slug/[marketSlug]`

Gets information about a single market by slug (the portion of the URL path after the username).

Requires no authorization.

Example request

https://manifold.markets/api/v0/slug/will-carrick-flynn-win-the-general

Response type: A FullMarket ; same as above.

`GET /v0/search-markets`

Search markets by keywords, limited to 100 results. Parameters:

terms: Optional. A space-separated list of keywords to search for.

Requires no authorization.

Example request

https://manifold.markets/api/v0/search-markets?terms=biden poop

Example response

[
  {
    "id": "qr759sZOfNCBV9o0cIDg",
    "creatorId": "2e6vTEJPk1dVs3xGvOBM2xkK2Q02",
    "creatorUsername": "frostmourn",
    "creatorName": "frostmourn",
    "createdTime": 1671067643426,
    "creatorAvatarUrl": "https://firebasestorage.googleapis.com/v0/b/mantic-markets.appspot.com/o/user-images%2Ffrostmourn%2FbpATR5uUGb.cloudfront?alt=media&token=ff031d9c-26e8-4b83-972f-ad1795633fac",
    "closeTime": 1672531140000,
    "question": "Will Biden poop in his pants again by EOY 2022?",
    "url": "https://manifold.markets/frostmourn/will-biden-poop-in-his-pants-again",
    "pool": {
      "NO": 199.4604480014367,
      "YES": 958.0024251946996
    },
    "probability": 0.0480391000210468,
    "p": 0.1950892350158,
    "totalLiquidity": 290,
    "outcomeType": "BINARY",
    "mechanism": "cpmm-1",
    "volume": 1165.294619742559,
    "volume24Hours": 0,
    "isResolved": true,
    "resolution": "NO",
    "resolutionTime": 1675498119366,
    "resolutionProbability": 0.05,
    "lastUpdatedTime": 1675498117432,
    "description": {
      "content": [
        {
          "content": [
            {
              "marks": [
                {
                  "attrs": {
                    "href": "https://www.opindia.com/2021/10/poopypantsbiden-trend-twitter-rumours-joe-biden-suffering-bathroom-accident-vatican/",
                    "target": "_blank"
                  },
                  "type": "link"
                }
              ],
              "text": "https://www.opindia.com/2021/10/poopypantsbiden-trend-twitter-rumours-joe-biden-suffering-bathroom-accident-vatican/",
              "type": "text"
            }
          ],
          "type": "paragraph"
        },
        {
          "attrs": {
            "src": "https://firebasestorage.googleapis.com/v0/b/mantic-markets.appspot.com/o/user-images%2Fdefault%2FagMgCBTkIa.jpg?alt=media&token=4d57e1c1-8264-45f7-bda5-db43b23f398e"
          },
          "type": "image"
        },
        {
          "content": [
            {
              "text": "Market resolves to \"yes\" if Biden pooped in his pants again by the end of 2022",
              "type": "text"
            }
          ],
          "type": "paragraph"
        },
        {
          "content": [
            {
              "text": "Market resolves to \"no\" if Biden has not pooped in his pants again by the end of 2022",
              "type": "text"
            }
          ],
          "type": "paragraph"
        }
      ],
      "type": "doc"
    },
    "coverImageUrl": "https://firebasestorage.googleapis.com/v0/b/mantic-markets.appspot.com/o/dream%2FxPIOqK99-m.png?alt=media&token=30a61355-fc83-4d98-9197-f99db72e8b54",
    "textDescription": "https://www.opindia.com/2021/10/poopypantsbiden-trend-twitter-rumours-joe-biden-suffering-bathroom-accident-vatican/\n\n[image]Market resolves to \"yes\" if Biden pooped in his pants again by the end of 2022\n\nMarket resolves to \"no\" if Biden has not pooped in his pants again by the end of 2022"
  }
]

Response type: Array of FullMarket.

// A complete market, along with answers (for free response markets)
type FullMarket = LiteMarket & {
  answers?: Answer[] // dpm-2 markets only
  description: JSONContent // Rich text content. See https://tiptap.dev/guide/output#option-1-json
  textDescription: string // string description without formatting, images, or embeds
  groupSlugs?: string[] // groups which the market is a part of
}

`GET /v0/users`

Lists all users, ordered by creation date descending.

Parameters:

limit: Optional. How many users to return. The maximum is 1000 and the default is 500.
before: Optional. The ID of the user before which the list will start. For example, if you ask for the most recent 10 users, and then perform a second query for 10 more users with before=[the id of the 10th user], you will get users 11 through 20.

Requires no authorization.

Example request

https://manifold.markets/api/v0/users?limit=1

Example response

[
  {
    "id": "igi2zGXsfxYPgB0DJTXVJVmwCOr2",
    "createdTime": 1639011767273,
    "name": "Austin",
    "username": "Austin",
    "url": "https://manifold.markets/Austin",
    "avatarUrl": "https://lh3.googleusercontent.com/a-/AOh14GiZyl1lBehuBMGyJYJhZd-N-mstaUtgE4xdI22lLw=s96-c",
    "bio": "I build Manifold! Always happy to chat; reach out on Discord or find a time on https://calendly.com/austinchen/manifold!",
    "bannerUrl": "https://images.unsplash.com/photo-1501523460185-2aa5d2a0f981?ixlib=rb-1.2.1&ixid=MnwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8&auto=format&fit=crop&w=1531&q=80",
    "website": "https://blog.austn.io",
    "twitterHandle": "akrolsmir",
    "discordHandle": "akrolsmir#4125",
    "balance": 9122.607163564959,
    "totalDeposits": 10339.004780544328,
    "totalPnLCached": 9376.601262721899
  }
]

Response type: Array of LiteUser

// Basic information about a user
type LiteUser = {
  id: string // user's unique id
  createdTime: number

  name: string // display name, may contain spaces
  username: string // username, used in urls
  url: string // link to user's profile
  avatarUrl?: string

  bio?: string
  bannerUrl?: string
  website?: string
  twitterHandle?: string
  discordHandle?: string

  // Note: the following are here for convenience only and may be removed in the future.
  balance: number
  totalDeposits: number
  totalPnLCached: number
}

`POST /v0/bet`

Places a new bet on behalf of the authorized user.

Parameters:

amount: Required. The amount to bet, in mana, before fees.
contractId: Required. The ID of the contract (market) to bet on.
outcome: Required. The outcome to bet on. For binary markets, this is YES or NO. For free response markets, this is the ID of the free response answer. For numeric markets, this is a string representing the target bucket, and an additional value parameter is required which is a number representing the target value. (Bet on numeric markets at your own peril.)
limitProb: Optional. A number between 0.01 and 0.99 inclusive representing the limit probability for your bet (i.e. 1% to 99% — multiply by 100 for the probability percentage). The bet will execute immediately in the direction of outcome, but not beyond this specified limit. If not all the bet is filled, the bet will remain as an open offer that can later be matched against an opposite direction bet.
- For example, if the current market probability is 50%:
  - A M$10 bet on YES with limitProb=0.4 would not be filled until the market probability moves down to 40% and someone bets M$15 of NO to match your bet odds.
  - A M$100 bet on YES with limitProb=0.6 would fill partially or completely depending on current unfilled limit bets and the AMM's liquidity. Any remaining portion of the bet not filled would remain to be matched against in the future.
- An unfilled limit order bet can be cancelled using the cancel API.
expiresAt: Optional. A Unix timestamp (in milliseconds) at which the limit bet should be automatically canceled.

Example request:

$ curl https://manifold.markets/api/v0/bet -X POST -H 'Content-Type: application/json' \
    -H 'Authorization: Key {...}' \
    --data-raw '{"amount":1, \
                 "outcome":"YES", \
                 "contractId":"{...}"}'

Response type: A Bet.

`POST /v0/bet/cancel/[id]`

Cancel the limit order of a bet with the specified id. If the bet was unfilled, it will be cancelled so that no other bets will match with it. This action is irreversible.

`POST /v0/market`

Creates a new market on behalf of the authorized user.

Note: this costs mana. If you have insufficient mana, this call will return an error. The cost to create each type of market is:

Market Type	Creation Cost
BINARY	M$50
PSEUDO_NUMERIC	M$250
FREE_RESPONSE	M$100
MULTIPLE_CHOICE	M$100

Parameters:

outcomeType: Required. One of BINARY, FREE_RESPONSE, MULTIPLE_CHOICE, or PSEUDO_NUMERIC.
question: Required. The headline question for the market.
description: Optional. A long description describing the rules for the market.
- Note: string descriptions do not turn into links, mentions, formatted text. You may instead use descriptionMarkdown or descriptionHtml for rich text formatting.
closeTime: Optional. The time at which the market will close, represented as milliseconds since the epoch. Defaults to 7 days from now.
visibility: Optional. One of public (default) or unlisted. Controls whether the market can be shown on homepage and in search results.
groupId: Optional. A group to create this market under.

For binary markets, you must also provide:

initialProb: An initial probability for the market, between 1 and 99.

For numeric markets, you must also provide:

min: The minimum value that the market may resolve to.
max: The maximum value that the market may resolve to.
isLogScale: If true, your numeric market will increase exponentially from min to max.
initialValue: An initial value for the market, between min and max, exclusive.

For multiple choice markets, you must also provide:

answers: An array of strings, each of which will be a valid answer for the market.

Example request:

$ curl https://manifold.markets/api/v0/market -X POST -H 'Content-Type: application/json' \
    -H 'Authorization: Key {...}'
    --data-raw '{"outcomeType":"BINARY", \
                 "question":"Is there life on Mars?", \
                 "description":"I'm not going to type some long ass example description.", \
                 "closeTime":1700000000000, \
                 "initialProb":25}'

`POST /v0/market/[marketId]/add-liquidity`

Adds a specified amount of liquidity into the market.

amount: Required. The amount of liquidity to add, in M$.

`POST /v0/market/[marketId]/close`

Closes a market on behalf of the authorized user.

closeTime: Optional. Milliseconds since the epoch to close the market at. If not provided, the market will be closed immediately. Cannot provide close time in the past.

`POST /v0/market/[marketId]/group`

Add or remove a market to/from a group.

groupId: Required. Id of the group. Must be admin/moderator/creator of group if curated/private. Must be market creator or trustworthyish if group is public.
remove: Optional. Set to true to remove the market from the group.

`POST /v0/market/[marketId]/resolve`

Resolves a market on behalf of the authorized user.

Parameters:

For binary markets:

outcome: Required. One of YES, NO, MKT, or CANCEL.
probabilityInt: Optional. The probability to use for MKT resolution.

For free response or multiple choice markets:

outcome: Required. One of MKT, CANCEL, or a number indicating the answer index.
resolutions: An array of { answer, pct } objects to use as the weights for resolving in favor of multiple free response options. Can only be set with MKT outcome. Note that the total weights must add to 100.

For numeric markets:

outcome: Required. One of CANCEL, or a number indicating the selected numeric bucket ID.
value: The value that the market resolves to.
probabilityInt: Required if value is present. Should be equal to
- If log scale: log10(value - min + 1) / log10(max - min + 1)
- Otherwise: (value - min) / (max - min)

Example request:

# Resolve a binary market
$ curl https://manifold.markets/api/v0/market/{marketId}/resolve -X POST \
    -H 'Content-Type: application/json' \
    -H 'Authorization: Key {...}' \
    --data-raw '{"outcome": "YES"}'

# Resolve a binary market with a specified probability
$ curl https://manifold.markets/api/v0/market/{marketId}/resolve -X POST \
    -H 'Content-Type: application/json' \
    -H 'Authorization: Key {...}' \
    --data-raw '{"outcome": "MKT", \
                 "probabilityInt": 75}'

# Resolve a free response market with a single answer chosen
$ curl https://manifold.markets/api/v0/market/{marketId}/resolve -X POST \
    -H 'Content-Type: application/json' \
    -H 'Authorization: Key {...}' \
    --data-raw '{"outcome": 2}'

# Resolve a free response market with multiple answers chosen
$ curl https://manifold.markets/api/v0/market/{marketId}/resolve -X POST \
    -H 'Content-Type: application/json' \
    -H 'Authorization: Key {...}' \
    --data-raw '{"outcome": "MKT", \
                 "resolutions": [ \
                   {"answer": 0, "pct": 50}, \
                   {"answer": 2, "pct": 50} \
                 ]}'

`POST /v0/market/[marketId]/sell`

Sells some quantity of shares in a binary market on behalf of the authorized user.

Parameters:

outcome: Optional. One of YES, or NO. If you leave it off, and you only own one kind of shares, you will sell that kind of shares.
shares: Optional. The amount of shares to sell of the outcome given above. If not provided, all the shares you own will be sold.

Example request:

$ curl https://manifold.markets/api/v0/market/{marketId}/sell -X POST \
    -H 'Content-Type: application/json' \
    -H 'Authorization: Key {...}' \
    --data-raw '{"outcome": "YES", "shares": 10}'

Response type: A Bet, with an additional "status": "success" field.

`POST /v0/comment`

Creates a comment in the specified market. Only supports top-level comments for now.

Parameters:

contractId: Required. The ID of the market to comment on.
content: The comment to post, formatted as TipTap json, OR
html: The comment to post, formatted as an HTML string, OR
markdown: The comment to post, formatted as a markdown string.

`GET /v0/comments`

Gets a list of comments for a contract, ordered by creation date descending.

Parameters:

contractId: Optional. Which contract to read comments for. Either an ID or slug must be specified.
contractSlug: Optional.

Requires no authorization.

`GET /v0/bets`

Gets a list of bets, ordered by creation date descending.

Parameters:

userId: Optional. If set, the response will include only bets created by this user.
username: Optional. If set, the response will include only bets created by this user.
contractId: Optional. If set, the response will only include bets on this contract.
contractSlug: Optional. If set, the response will only include bets on this contract.
limit: Optional. How many bets to return. The maximum and the default are 1000.
before: Optional. The ID of the bet before which the list will start. For example, if you ask for the most recent 10 bets, and then perform a second query for 10 more bets with before=[the id of the 10th bet], you will get bets 11 through 20.

Requires no authorization.

Example request

https://manifold.markets/api/v0/bets?username=ManifoldMarkets&contractSlug=will-i-be-able-to-place-a-limit-ord

Response type: A Bet[].

Example response

[
  // Limit bet, partially filled.
  {
    "isFilled": false,
    "amount": 15.596681605353808,
    "userId": "IPTOzEqrpkWmEzh6hwvAyY9PqFb2",
    "contractId": "Tz5dA01GkK5QKiQfZeDL",
    "probBefore": 0.5730753474948571,
    "isCancelled": false,
    "outcome": "YES",
    "fees": { "creatorFee": 0, "liquidityFee": 0, "platformFee": 0 },
    "shares": 31.193363210707616,
    "limitProb": 0.5,
    "id": "yXB8lVbs86TKkhWA1FVi",
    "loanAmount": 0,
    "orderAmount": 100,
    "probAfter": 0.5730753474948571,
    "createdTime": 1659482775970,
    "fills": [
      {
        "timestamp": 1659483249648,
        "matchedBetId": "MfrMd5HTiGASDXzqibr7",
        "amount": 15.596681605353808,
        "shares": 31.193363210707616
      }
    ]
  },
  // Normal bet (no limitProb specified).
  {
    "shares": 17.350459904608414,
    "probBefore": 0.5304358279113885,
    "isFilled": true,
    "probAfter": 0.5730753474948571,
    "userId": "IPTOzEqrpkWmEzh6hwvAyY9PqFb2",
    "amount": 10,
    "contractId": "Tz5dA01GkK5QKiQfZeDL",
    "id": "1LPJHNz5oAX4K6YtJlP1",
    "fees": {
      "platformFee": 0,
      "liquidityFee": 0,
      "creatorFee": 0.4251333951457593
    },
    "isCancelled": false,
    "loanAmount": 0,
    "orderAmount": 10,
    "fills": [
      {
        "amount": 10,
        "matchedBetId": null,
        "shares": 17.350459904608414,
        "timestamp": 1659482757271
      }
    ],
    "createdTime": 1659482757271,
    "outcome": "YES"
  }
]

Changelog

2023-05-15: Change the response of the /market/{marketId}/sell POST endpoint from {"status": "success"} to a full Bet, with an additional "status": "success" field.
2023-04-03: Add /market/[marketId]/group POST endpoint.
2023-03-21: Add /market/[marketId]/positions and /search-markets endpoints
2022-11-22: Update /market GET to remove bets and comments
2022-10-17: Update /market POST to allow visibility and groupId; mark closeTime as optional; remove tags
2022-09-24: Expand market POST docs to include new market types (PSEUDO_NUMERIC, MULTIPLE_CHOICE)
2022-07-15: Add user by username and user by ID APIs
2022-06-08: Add paging to markets endpoint
2022-06-05: Add new authorized write endpoints
2022-02-28: Add resolutionTime to markets, change closeTime definition
2022-02-19: Removed user IDs from bets
2022-02-17: Released our v0 API, with /markets, /market/[marketId], and /slug/[slugId]

Manifold API

caution

General notes​

Usage Guidelines​

Fees​

Trade history dumps​

Endpoints​

GET /v0/user/[username]​

GET /v0/user/by-id/[id]​

GET /v0/me​

GET /v0/groups​

GET /v0/group/[slug]​

GET /v0/group/by-id/[id]​

GET /v0/group/by-id/[id]/markets​

GET /v0/markets​

GET /v0/market/[marketId]​

GET /v0/market/[marketId]/positions​

GET /v0/slug/[marketSlug]​

GET /v0/search-markets​

GET /v0/users​

POST /v0/bet​

POST /v0/bet/cancel/[id]​

POST /v0/market​

POST /v0/market/[marketId]/add-liquidity​

POST /v0/market/[marketId]/close​

POST /v0/market/[marketId]/group​

POST /v0/market/[marketId]/resolve​

POST /v0/market/[marketId]/sell​

POST /v0/comment​

GET /v0/comments​

GET /v0/bets​

Changelog​

General notes

Usage Guidelines

Fees

Trade history dumps

Endpoints

`GET /v0/user/[username]`

`GET /v0/user/by-id/[id]`

`GET /v0/me`

`GET /v0/groups`

`GET /v0/group/[slug]`

`GET /v0/group/by-id/[id]`

`GET /v0/group/by-id/[id]/markets`

`GET /v0/markets`

`GET /v0/market/[marketId]`

`GET /v0/market/[marketId]/positions`

`GET /v0/slug/[marketSlug]`

`GET /v0/search-markets`

`GET /v0/users`

`POST /v0/bet`

`POST /v0/bet/cancel/[id]`

`POST /v0/market`

`POST /v0/market/[marketId]/add-liquidity`

`POST /v0/market/[marketId]/close`

`POST /v0/market/[marketId]/group`

`POST /v0/market/[marketId]/resolve`

`POST /v0/market/[marketId]/sell`

`POST /v0/comment`

`GET /v0/comments`

`GET /v0/bets`

Changelog