> ## Documentation Index > Fetch the complete documentation index at: https://docs.fynn.eu/llms.txt > Use this file to discover all available pages before exploring further. # Create a checkout link > Create a checkout link that sells one tier of the plan. The returned url is the public entry point that creates a cart and redirects the buyer to the customerfront of the sales channel. ## OpenAPI ````yaml post /api/plans/{id}/checkout-links openapi: 3.1.0 info: title: Fynn V2 Plans API version: 2026-06 description: >- REST API for the Fynn V2 Plans. Use it to define plans with upgrade and downgrade tiers, sell them through checkout links, and let customers switch tiers from your customer portal. All amounts use the minor or decimal representation documented per field. Authenticate setup endpoints with an API token and customer endpoints with a customer token. servers: - url: https://coreapi.io description: Production - url: https://preview.coreapi.io description: Sandbox security: - ApiToken: [] tags: - name: Plans description: Create and manage plans, tiers and items. - name: Checkout Links description: Sell a plan tier through a hosted checkout link. - name: Plan switching (customer) description: Customer facing upgrade and downgrade between tiers. paths: /api/plans/{id}/checkout-links: post: tags: - Checkout Links summary: Create a checkout link description: >- Create a checkout link that sells one tier of the plan. The returned url is the public entry point that creates a cart and redirects the buyer to the customerfront of the sales channel. operationId: createPlanCheckoutLink parameters: - name: id in: path required: true schema: type: string format: uuid example: 1280792f-4e23-793d-8e9c-3a1bf36630bd description: The plan UUID. requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/CreatePlanCheckoutLinkInput' example: planTierId: f5ece259-08ea-77a4-8bd9-9f3a9ed9e246 couponsAllowed: false isEnabled: true salesChannel: default responses: '201': description: The created checkout link. content: application/json: schema: $ref: '#/components/schemas/PlanCheckoutLink' '401': description: Authentication is missing or the token is invalid. content: application/problem+json: schema: $ref: '#/components/schemas/ProblemError' '403': description: The token is valid but lacks the required permission. content: application/problem+json: schema: $ref: '#/components/schemas/ProblemError' '404': description: The requested resource does not exist for this Organisation. content: application/problem+json: schema: $ref: '#/components/schemas/ProblemError' '409': description: >- The request conflicts with the current state, for example a duplicate plan code or checkout link slug. content: application/problem+json: schema: $ref: '#/components/schemas/ProblemError' '422': description: The request failed validation or a business rule was violated. content: application/problem+json: schema: oneOf: - $ref: '#/components/schemas/ValidationError' - $ref: '#/components/schemas/ProblemError' components: schemas: CreatePlanCheckoutLinkInput: type: object required: - planTierId properties: planTierId: type: string description: UUID of the tier the checkout link sells. Must belong to this plan. slug: type: string minLength: 3 maxLength: 64 pattern: ^[a-z0-9]([a-z0-9-]*[a-z0-9])?$ nullable: true description: Custom URL slug. When omitted a unique slug is generated. couponsAllowed: type: boolean default: false description: Whether buyers may enter a coupon code during checkout. isEnabled: type: boolean default: true description: Whether the link is active and reachable. salesChannel: type: string nullable: true description: >- Sales channel as a UUID or as a technical name such as default. When omitted the active channel of the request is used, otherwise the Organisation default channel. PlanCheckoutLink: type: object properties: id: type: string format: uuid example: 1280792f-4e23-793d-8e9c-3a1bf36630bd slug: type: string example: pro-plan-pro planTierId: type: string planTierName: type: string example: Pro couponsAllowed: type: boolean isEnabled: type: boolean url: type: string format: uri description: Public checkout URL that creates a cart and redirects the buyer. example: https://coreapi.io/checkout-link/pro-plan-pro/cart createdAt: type: string format: date-time updatedAt: type: string format: date-time salesChannel: $ref: '#/components/schemas/SalesChannelReference' ProblemError: type: object description: >- Problem detail error body (application/problem+json). Additional members may be present depending on the error. properties: status: type: integer example: 404 type: type: string description: Stable machine readable error key. example: PLAN__NOT_FOUND title: type: string example: An error occurred detail: type: string example: Plan not found. required: - status - type - title - detail ValidationError: type: object description: >- Validation error body (application/problem+json) returned when input fails field level validation. properties: status: type: integer example: 422 type: type: string example: https://tools.ietf.org/html/rfc2616#section-10 title: type: string example: Validation Failed violations: type: array items: type: object properties: propertyPath: type: string example: tiers[0].name message: type: string example: This value should not be blank. code: type: string nullable: true required: - status - type - title - violations SalesChannelReference: type: object nullable: true properties: id: type: string name: type: string description: Stable technical name of the sales channel. example: default brandName: type: string description: Display brand name of the sales channel. example: Pro Plan securitySchemes: ApiToken: type: http scheme: bearer description: >- Organisation API token. Send it as Authorization: Bearer api_... The token is scoped to a single Organisation. ````