Polymarket CLOB Trade API

Order placement and management on the central-limit order book.

Documentation GitHub OpenAPI

Operations 1

POST /order Post a new order #

Specifications

https://raw.githubusercontent.com/api-evangelist/polymarket/refs/heads/main/openapi/polymarket-clob-trade-api-openapi.yml

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OpenAPI Specification

openapi: 3.2.0
info:
  title: Polymarket APIs (CLOB and Gamma) CLOB Market Data CLOB Trade API
  version: '1.0'
  description: "Polymarket exposes several HTTP APIs documented at\nhttps://docs.polymarket.com/:\n\n  * CLOB API (`https://clob.polymarket.com`) for order book,\n    trading, and pricing operations.\n  * Gamma API (`https://gamma-api.polymarket.com`) for read-only\n    market, event, and metadata access.\n\nThis specification captures a representative subset of endpoints\nfrom both surfaces. CLOB trading endpoints require the\nPOLY_API_KEY / POLY_ADDRESS / POLY_SIGNATURE / POLY_PASSPHRASE /\nPOLY_TIMESTAMP header set; Gamma endpoints are fully public.\n"
  contact:
    name: Polymarket Documentation
    url: https://docs.polymarket.com/
servers:
- url: https://clob.polymarket.com
  description: Polymarket CLOB API
- url: https://clob-staging.polymarket.com
  description: Polymarket CLOB staging
- url: https://gamma-api.polymarket.com
  description: Polymarket Gamma API
tags:
- name: CLOB Trade
  description: Order placement and management on the central-limit order book.
paths:
  /order:
    post:
      tags:
      - CLOB Trade
      operationId: postNewOrder
      summary: Post a new order
      description: 'Submit a new signed order to the Polymarket CLOB.

        Requires the full POLY_* signed-request header set.

        '
      servers:
      - url: https://clob.polymarket.com
      - url: https://clob-staging.polymarket.com
      security:
      - polyApiSignature: []
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/OrderRequest'
      responses:
        '200':
          description: Order acknowledgement
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/OrderResponse'
components:
  schemas:
    OrderResponse:
      type: object
      properties:
        success:
          type: boolean
        errorMsg:
          type: string
        orderID:
          type: string
        transactionsHashes:
          type: array
          items:
            type: string
        status:
          type: string
    Order:
      type: object
      required:
      - maker
      - signer
      - tokenId
      - makerAmount
      - takerAmount
      - side
      - expiration
      - timestamp
      - builder
      - signature
      - salt
      - signatureType
      properties:
        maker:
          type: string
          description: Wallet address of the order maker.
        signer:
          type: string
          description: Address that signed the order (may differ from maker for proxy signers).
        tokenId:
          type: string
          description: ERC-1155 token id for the outcome.
        makerAmount:
          type: string
        takerAmount:
          type: string
        side:
          type: string
          enum:
          - BUY
          - SELL
        expiration:
          type: string
          description: Unix expiration timestamp ('0' for none).
        timestamp:
          type: string
        builder:
          type: string
        signature:
          type: string
        salt:
          type: string
        signatureType:
          type: integer
    OrderRequest:
      type: object
      required:
      - order
      - owner
      properties:
        order:
          $ref: '#/components/schemas/Order'
        owner:
          type: string
          description: UUID of the API key owner.
        orderType:
          type: string
          enum:
          - GTC
          - FOK
          - GTD
          - FAK
          default: GTC
        deferExec:
          type: boolean
          default: false
        postOnly:
          type: boolean
          default: false
  securitySchemes:
    polyApiSignature:
      type: apiKey
      in: header
      name: POLY_API_KEY
      description: 'Polymarket CLOB authenticated trading endpoints require five

        headers: POLY_API_KEY, POLY_ADDRESS, POLY_SIGNATURE,

        POLY_PASSPHRASE, POLY_TIMESTAMP. Only POLY_API_KEY is modelled

        here because OpenAPI security schemes describe a single header

        each; in practice, all five must be sent on each request.

        '