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

# Get Certification URL

> Applies for a valid, time-limited "Sub-account Onboarding Hosted Page" URL on behalf of an institutional sub-account, with the institutional merchant as the main entity, to guide the sub-account holder through KYB certification.

## Overview

This page documents the `POST /payment/open/v1/certification/url` endpoint. The full schema, parameters, and examples are rendered from the linked OpenAPI definition above.

## Notes

* Authentication uses the standard GatePay signed headers.
* This endpoint retrieves the KYB certification page URL.
* The returned URL already includes the authentication token parameter and can be accessed directly.
* Institutional requests must include `X-GatePay-On-Behalf-Of` to specify the institutional sub-account to operate on.
* For shared signing rules, see [/api-reference/version/100/en/common/securityAndSignature](/api-reference/version/100/en/common/securityAndSignature).

## Important Notes

* The request body must include `expireSeconds` to specify the certification URL expiration time
* The token parameter in the URL contains authentication information and should be kept secure


## OpenAPI

````yaml api-reference/version/100/en/openapi/institutional-openapi.json POST /pay-cashier/open/v1/certification/url
openapi: 3.1.0
info:
  title: GatePay Institutional API
  description: >-
    Gate Pay Institution API documentation. Create and manage sub-accounts,
    finance, orders, payout, transfer, and more.
  license:
    name: MIT
  version: 1.0.0
servers:
  - url: https://openplatform.gateapi.io
security: []
paths:
  /pay-cashier/open/v1/certification/url:
    post:
      tags:
        - Institutional
      summary: 获取认证 URL
      operationId: getCertificationUrl
      parameters:
        - name: X-GatePay-On-Behalf-Of
          in: header
          required: true
          schema:
            type: string
          description: 机构子账户 ID
        - name: X-GatePay-Merchant-Id
          in: header
          required: true
          schema:
            type: string
          description: 商户 ID
        - name: X-GatePay-Certificate-ClientId
          in: header
          required: true
          schema:
            type: string
          description: 客户端 ID（证书专用）
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
                - expireSeconds
              properties:
                expireSeconds:
                  type: integer
                  description: 认证URL过期时间（秒）
                  example: 86400
                requestId:
                  type: string
                  description: 请求 ID，用于追踪请求来源（可选参数）
      responses:
        '200':
          description: 成功响应
          content:
            application/json:
              schema:
                type: object
                properties:
                  code:
                    type: string
                    example: '0'
                  message:
                    type: string
                    example: success
                  data:
                    type: object
                    properties:
                      authUrl:
                        type: string
                        description: 认证 URL
                      subAccountId:
                        type: integer
                        format: int64
                        description: 子账户 ID
                      expireTime:
                        type: integer
                        format: int64
                        description: 认证URL过期时间戳(毫秒)
                      requestId:
                        type: string
                        description: 请求 ID

````