Developers

Public billing API for invoices, clients, and webhooks.

Generate an API key in settings, send Bearer-authenticated requests, and subscribe to invoice lifecycle events.

Example request

Create a usage invoice.

curl -X POST https://your-domain.com/api/v1/invoices \
  -H "Authorization: Bearer ivc_..." \
  -H "Content-Type: application/json" \
  -d '{
    "clientId": "client_id",
    "lineItems": [
      { "type": "USAGE", "description": "API calls", "quantity": 25000, "unitPrice": 0.002 }
    ]
  }'

Bearer API keys

Keys are hashed before storage, revokable, and rate-limited per key.

Signed webhooks

JSON contracts

Responses follow data/message success envelopes and error/code failure envelopes.

Endpoints

POST/api/v1/invoicesCreate an invoice

GET/api/v1/invoicesList invoices

GET/api/v1/invoices/:idRetrieve an invoice

PATCH/api/v1/invoices/:idUpdate an invoice

POST/api/v1/invoices/:id/sendSend an invoice

GET/api/v1/clientsList clients

POST/api/v1/clientsCreate a client

Webhook Events

invoice.paid

Delivered as signed JSON with X-Invoicycle-Signature.

invoice.sent

Delivered as signed JSON with X-Invoicycle-Signature.

invoice.overdue

Delivered as signed JSON with X-Invoicycle-Signature.

Build path

Start with the free invoice workflow, then connect API automation.

Review pricing, integration options, and the OpenAPI contract before wiring production billing events into your app.

Integrations Pricing