> ## Documentation Index > Fetch the complete documentation index at: https://docs.base44.com/llms.txt > Use this file to discover all available pages before exploring further. # Create domain checkout link > This API is in beta. Endpoints, fields, and behavior may still change, so avoid depending on it in production. Creates a one-time checkout link for buying a domain through Base44. Not every workspace can buy domains through the API. For one that can't, the call is rejected and the domain has to be bought in the Base44 editor. Pass `domain` to open checkout on that domain, and check it first with [Check domain availability](/api-reference/check-domain-availability). Leave it out to open checkout on a domain search. The person who opens the link pays at checkout, and nothing is bought until they finish. The domain is then attached to the app once it's registered, and appears in [List custom domains](/api-reference/list-custom-domains). Each call returns a new link and buys nothing, so retrying is safe, including after a timeout. The call fails while the checkout provider is unavailable. Creating links is limited to 6 requests a minute and 20 an hour per caller. Some workspaces have a different limit. ## OpenAPI ````yaml /developers/references/app-management/app-management-openapi.json post /api/apps/{app_id}/custom-domains/purchase-url openapi: 3.1.0 info: title: Base44 App Management API version: 1.0.0 servers: - url: https://app.base44.com security: - PersonalAccessTokenAuth: [] paths: /api/apps/{app_id}/custom-domains/purchase-url: post: summary: Create domain checkout link description: >- This API is in beta. Endpoints, fields, and behavior may still change, so avoid depending on it in production. Creates a one-time checkout link for buying a domain through Base44. Not every workspace can buy domains through the API. For one that can't, the call is rejected and the domain has to be bought in the Base44 editor. Pass `domain` to open checkout on that domain, and check it first with [Check domain availability](/api-reference/check-domain-availability). Leave it out to open checkout on a domain search. The person who opens the link pays at checkout, and nothing is bought until they finish. The domain is then attached to the app once it's registered, and appears in [List custom domains](/api-reference/list-custom-domains). Each call returns a new link and buys nothing, so retrying is safe, including after a timeout. The call fails while the checkout provider is unavailable. Creating links is limited to 6 requests a minute and 20 an hour per caller. Some workspaces have a different limit. operationId: >- create_domain_purchase_url_api_apps__app_id__custom_domains_purchase_url_post parameters: - name: app_id in: path required: true schema: type: string description: ID of the app you're finding a domain for. title: App Id description: ID of the app you're finding a domain for. example: 6820f3a4e7b91d003c45a1f2 requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/DomainPurchaseUrlRequest' responses: '200': description: Successful Response content: application/json: schema: $ref: '#/components/schemas/DomainPurchaseUrl' '400': description: >- `domain` isn't a valid domain name, or you have reached the limit of 350 custom domains. '401': description: Missing or invalid credentials. '402': description: This workspace's plan doesn't include custom domains. '403': description: >- You don't have access to this app, or you used a workspace API key. These endpoints take a personal API key. '404': description: App not found. '409': description: >- This workspace can't buy domains through the API, so the purchase has to happen in the Base44 editor. '422': description: Validation Error content: application/json: schema: $ref: '#/components/schemas/HTTPValidationError' '429': description: Rate limit reached. Retry later. security: - PersonalAccessTokenAuth: - full_access components: schemas: DomainPurchaseUrlRequest: properties: domain: anyOf: - type: string - type: 'null' title: Domain description: >- Domain to open checkout on, such as `example.com`. Leave it out to open checkout on a domain search. example: nordwind-furniture.com offer_business_email: type: boolean title: Offer Business Email description: >- Whether checkout also offers a business email address on the domain after the purchase (`true`) or not (`false`). default: false example: false type: object title: DomainPurchaseUrlRequest DomainPurchaseUrl: properties: url: type: string title: Url description: >- Checkout link to open in the browser of the person who'll pay. Treat it as opaque. It works once, so create a new one for each checkout. example: >- https://checkout.example.com/session/7c1e9f2a4b8d4e6f9a3c5b7d1e2f4a6c type: object required: - url title: DomainPurchaseUrl description: A checkout link for buying a domain. HTTPValidationError: properties: detail: items: $ref: '#/components/schemas/ValidationError' type: array title: Detail type: object title: HTTPValidationError ValidationError: properties: loc: items: anyOf: - type: string - type: integer type: array title: Location msg: type: string title: Message type: type: string title: Error Type type: object required: - loc - msg - type title: ValidationError securitySchemes: PersonalAccessTokenAuth: type: http scheme: bearer description: >- Personal access token, sent as `Authorization: Bearer `. Each operation lists the permission it needs: `read_only` or `full_access`. A full-access token can call every operation. A read-only token can call only the operations that list `read_only`; anything else returns 403 `read_only_credential_route_not_allowed`. ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.