We never store your KSeF keys
Your government credentials are passed per request and held in-memory only for the duration of the call — never written to disk, never logged, never retained. You stay in control.
KSeF invoicing, one API call
Issue and fetch invoices in KSeF without hosting your government credentials — pass them per request, in-memory only. Test environment included on every plan.
What you get
One call to issue
POST your invoice data and get back a KSeF reference number and UPO receipt. The API handles FA(3) generation, signing, and submission internally.
Fetch your invoices
Query and download both sales and purchase invoices from KSeF by date range or reference. Useful for reconciliation, archival, and audit trails.
Test environment + numbering
The KSeF test environment is available on every plan. Test calls count toward your monthly quota just like production — use the 14-day free trial as your integration runway. Built-in invoice numbering means you can generate compliant series numbers without a separate tool.