Blockchair

Blockchair Broadcast API

Signed transaction broadcasting.

Documentation GitHub OpenAPI

Operations 1

POST /{chain}/push/transaction Broadcast a signed transaction #

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OpenAPI Specification

openapi: 3.2.0
info:
  title: Blockchair Address Dashboards Broadcast API
  description: The Blockchair API provides unified, multi-blockchain access to on-chain data across 40+ blockchains. It exposes per-chain dashboards (address, transaction, block), raw node data, network statistics, a SQL-like database query interface (blocks, transactions, outputs, addresses), and transaction broadcasting. Requests are authenticated with an optional `key` query parameter; up to 1440 requests per day are allowed without a key for personal or testing use.
  termsOfService: https://blockchair.com/api/docs
  contact:
    name: Blockchair Support
    url: https://github.com/Blockchair/Blockchair.Support
  version: 2.0.80
servers:
- url: https://api.blockchair.com
  description: Blockchair production API
security:
- apiKey: []
tags:
- name: Broadcast
  description: Signed transaction broadcasting.
paths:
  /{chain}/push/transaction:
    post:
      operationId: broadcastTransaction
      tags:
      - Broadcast
      summary: Broadcast a signed transaction
      description: Relays a signed, raw transaction to the network of the selected chain.
      parameters:
      - $ref: '#/components/parameters/chain'
      - $ref: '#/components/parameters/key'
      requestBody:
        required: true
        content:
          application/x-www-form-urlencoded:
            schema:
              type: object
              required:
              - data
              properties:
                data:
                  type: string
                  description: The signed, raw transaction in hexadecimal form.
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BroadcastResponse'
components:
  schemas:
    Context:
      type: object
      description: Metadata describing the request, cost, and server state.
      properties:
        code:
          type: integer
          example: 200
        source:
          type: string
        results:
          type: integer
        state:
          type: integer
          description: Current best block height of the chain.
        cache:
          type: object
        api:
          type: object
          properties:
            version:
              type: string
            last_major_update:
              type: string
            next_major_update:
              type: string
        request_cost:
          type: number
          description: Number of API request units this call consumed.
        time:
          type: number
    BroadcastResponse:
      type: object
      properties:
        data:
          type: object
          properties:
            transaction_hash:
              type: string
              description: The hash of the broadcast transaction.
        context:
          $ref: '#/components/schemas/Context'
  parameters:
    key:
      name: key
      in: query
      required: false
      description: API key.
      schema:
        type: string
    chain:
      name: chain
      in: path
      required: true
      description: Blockchain slug (e.g. bitcoin, ethereum, litecoin, dogecoin).
      schema:
        type: string
        example: bitcoin
  securitySchemes:
    apiKey:
      type: apiKey
      in: query
      name: key
      description: Optional API key passed as the `key` query parameter. Up to 1440 requests per day are allowed without a key for personal/testing use.