> ## Documentation Index
> Fetch the complete documentation index at: https://second.tech/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Send on-chain from Ark balance

> Sends the specified amount to an on-chain address using the wallet's off-chain Ark balance. The on-chain transaction fee is paid on top of the specified amount. Internally creates an out-of-round transaction to consolidate VTXOs into the exact amount needed, then cooperatively sends the on-chain payment via the Ark server. To offboard entire VTXOs without specifying an amount, use `offboard/vtxos` or `offboard/all` instead.



## OpenAPI

````yaml https://gitlab.com/ark-bitcoin/bark/-/raw/master/bark-rest/openapi.json post /api/v1/wallet/send-onchain
openapi: 3.1.0
info:
  title: barkd REST API
  description: >-
    A simple REST API for barkd, a wallet daemon for integrating bitcoin
    payments into your app over HTTP. Supports self-custodial Lightning, Ark,
    and on-chain out of the box.


    barkd is a long-running daemon best suited for always-on or
    high-connectivity environments like nodes, servers, desktops, and
    point-of-sale terminals.


    All endpoints return JSON. Amounts are denominated in satoshis.
  contact:
    name: Second Team
    email: hello@second.tech
  license:
    name: MIT
    identifier: MIT
  version: 0.1.4
servers: []
security:
  - bearer: []
tags:
  - name: boards
    description: Move on-chain bitcoin onto the Ark protocol.
  - name: exits
    description: Move bitcoin back on-chain without server cooperation.
  - name: fees
    description: Estimate fees for wallet operations before executing them.
  - name: lightning
    description: Create Lightning invoices and track receives.
  - name: onchain
    description: Manage barkd's on-chain bitcoin wallet.
  - name: wallet
    description: Manage Ark balances and VTXOs, send payments via Ark, LN, and on-chain.
  - name: bitcoin
    description: Query bitcoin network data.
  - name: notifications
    description: Receive real-time notifications from barkd.
paths:
  /api/v1/wallet/send-onchain:
    post:
      tags:
        - wallet
      summary: Send on-chain from Ark balance
      description: >-
        Sends the specified amount to an on-chain address using the wallet's
        off-chain Ark balance. The on-chain transaction fee is paid on top of
        the specified amount. Internally creates an out-of-round transaction to
        consolidate VTXOs into the exact amount needed, then cooperatively sends
        the on-chain payment via the Ark server. To offboard entire VTXOs
        without specifying an amount, use `offboard/vtxos` or `offboard/all`
        instead.
      operationId: send_onchain
      requestBody:
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/SendOnchainRequest'
        required: true
      responses:
        '200':
          description: Returns the offboard transaction id
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/OffboardResult'
        '500':
          description: Internal server error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/InternalServerError'
components:
  schemas:
    SendOnchainRequest:
      type: object
      required:
        - destination
        - amount_sat
      properties:
        amount_sat:
          type: integer
          format: int64
          description: >-
            The amount (in satoshis) to be received by `destination` onchain.
            Must be

            >= [P2TR_DUST](bitcoin_ext::P2TR_DUST). Server-configured fees laid
            out in

            [OffboardFees](crate::cli::fees::OffboardFees) will be added on top
            of this amount.
          minimum: 0
        destination:
          type: string
          description: The destination Bitcoin address
    OffboardResult:
      type: object
      required:
        - offboard_txid
      properties:
        offboard_txid:
          type: string
          description: The transaction id of the offboard transaction
    InternalServerError:
      type: object
      required:
        - message
      properties:
        message:
          type: string
  securitySchemes:
    bearer:
      type: http
      scheme: bearer
      bearerFormat: AuthToken
      description: Base64url-encoded auth token

````