Online Signatures · API

API signature plans

Connect signature generation to your apps, sites and bots. Pay only for volume — pick a plan with the calculator below. No tie to the document plan.

Fast generation Secure keys PNG · SVG · JPG · PDF Monthly limit reset
API Start
5 000 signatures / mo
  • Up to 4 API keys
  • 50 requests / minute
  • Formats: PNG
  • Quality: 1× only
  • Limit resets every month
Payments are temporarily unavailable
Popular
API Pro
60 000 signatures / mo
  • Up to 5 API keys
  • 300 requests / minute
  • Formats: PNG · SVG · JPG
  • Quality: 1×, 2× and 4×
  • Limit resets every month
Payments are temporarily unavailable
API Business
250 000 signatures / mo
  • Up to 15 API keys
  • 5 000 requests / minute
  • Formats: PNG · SVG · JPG · PDF
  • Quality: 1×, 2× and 4×
  • Limit resets every month
Payments are temporarily unavailable
API Scale
1 000 000 signatures / mo
  • Up to 50 API keys
  • 3 000 requests / minute
  • Formats: PNG · SVG · JPG · PDF
  • Quality: 1×, 2× and 4×
  • Limit resets every month
Payments are temporarily unavailable

How it works

Api Documentation

1. Choose an API plan, then pay for it (separate from the document plan).
2. In your cabinet (/api-control) create an API key.
3. Embed the key in your app, site or bot — a POST request returns the signature image.
4. Track usage in real time; the limit resets every month.

Over the limit? Requests are politely paused until next month or until you move to a higher plan — no surprise bills.

Frequently asked questions

Which formats does the API return?
PNG (transparent background) on every plan. SVG and JPG from the Pro plan, PDF on the higher plans. You pick the format with the format parameter in the request; the image arrives as data:...;base64 in the data.signature field.
What does the quality parameter do?
Add "quality": 1, 2 or 4 to the request to get a sharper, more detailed signature. 1× is standard; 2× and 4× are crisper. Start includes 1×; Pro and higher plans include 1×, 2× and 4×. It does not use extra quota.
Do I need a PRO document plan to use the API?
No. The API plan is a separate product — you can use the API on its own.
What if I send more requests than my plan allows?
Extra requests are refused (overuse protection) — just move up to a higher plan. No surprise bills.
Can I change my plan?
Yes, at any time — up or down, from the next billing cycle.
Does a failed request count?
No — the limit is only spent on successfully generated signatures.