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

# Check token ownership

> 
    Checks if a user owns a specific token by querying token balances across chains.
    Returns ownership status and balance with caching for performance.
  



## OpenAPI

````yaml post /check-token-ownership
openapi: 3.0.3
info:
  title: Token Layer API
  version: 1.0.0
  description: |2-

          Token Layer is an omnichain token trading platform where users can create and trade tokens across multiple chains.

          This API provides comprehensive access to token operations, trading, earnings,
          blockchain transactions, and portfolio management.

          ## Base URL
          All endpoints are accessed via: `https://api.tokenlayer.network/{endpoint}`

          ## Authentication
          Most endpoints require authentication using an JWT token or API key passed as a Bearer token in the Authorization header.

          ## Rate Limiting
          API calls are rate limited per user. Please implement appropriate backoff strategies.
        
  contact:
    name: Token Layer API Support
    url: https://app.tokenlayer.network
servers:
  - url: https://api.tokenlayer.network/functions/v1
    description: Production server
  - url: https://api.tokenlayer.network/functions/v1
    description: Staging server
security: []
tags:
  - name: Tokens
    description: Token creation, browsing, search, trading, and price operations
  - name: Transactions
    description: Blockchain transactions (send, tip, ownership checks)
paths:
  /check-token-ownership:
    post:
      tags:
        - Tokens
      summary: Check token ownership
      description: |2-

            Checks if a user owns a specific token by querying token balances across chains.
            Returns ownership status and balance with caching for performance.
          
      operationId: checkTokenOwnership
      requestBody:
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CheckTokenOwnershipRequest'
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/CheckTokenOwnershipResponse'
        '400':
          description: Bad request - Invalid parameters
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '500':
          description: Internal server error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
components:
  schemas:
    CheckTokenOwnershipRequest:
      type: object
      properties:
        token_id:
          type: string
          format: uuid
        user_address:
          type: string
          pattern: ^0x[a-fA-F0-9]{40}$
        user_id:
          type: string
          format: uuid
      required:
        - token_id
        - user_address
    CheckTokenOwnershipResponse:
      type: object
      properties:
        success:
          type: boolean
          enum:
            - true
        is_holder:
          type: boolean
        balance:
          type: number
        cached:
          type: boolean
      required:
        - success
        - is_holder
        - balance
    Error:
      type: object
      properties:
        success:
          type: boolean
          enum:
            - false
        error:
          type: string
      required:
        - success
        - error
      description: Error response

````