Kfinx API
Clear documentation. Straightforward integration.
Bill from your till, your site or your back office. Create an invoice and get a pay link back in one call, then read payments and balances when you need them.
Authentication
Every request carries an integration key. A key belongs to one business and can only ever read or write that business’s data.
Getting a key
In Kfinx, open Admin → API keys, add an integration, and generate a key. You will see it once. Keys are prefixed wb_. Anyone who administers a business can create keys for it — you do not need to ask us.
Sending it
Either header works. Pick one:
# The Authorization header…
Authorization: Api-Key wb_live_7Kd93mZq…
# …or a dedicated header, if your client reserves Authorization
X-Api-Key: wb_live_7Kd93mZq…Not Bearer. Kfinx signs users in with JWTs that already claim the Bearer scheme, so a key sent as Authorization: Bearer … is rejected before it reaches your integration. Use Api-Key, or the X-Api-Key header.
Scopes
A key grants exactly what you ticked when you made it.
| Scope | Lets you |
|---|---|
| invoices:read | List and fetch invoices |
| invoices:write | Create and issue invoices, mint pay links |
Create an invoice
Create and issue an invoice from your own application. Kfinx handles the billing record and returns the invoice data your system needs.
POST/api/billing/api/invoices/
{
"customer": "3f9a…",
"lines": [
{ "item": "a71c…", "qty": 40, "unit_price": 850 }
]
}Send your customer somewhere to pay
Mint a pay link for an issued invoice and send it to the customer however you already reach them.
POST/api/billing/api/invoices/{id}/pay-link/
Fetch one back
Read an invoice with its payments and outstanding balance.
GET/api/billing/api/invoices/{id}/