Inkspan › Guides › HTML to PDF API

HTML to PDF API

Turn any HTML string into a pixel-faithful PDF. No Chromium in your container, no font installs, no scaling headaches — POST your HTML and stream back a PDF.

Because rendering uses CSS paged media rather than a browser screenshot, headers, footers, and page counters work the way print CSS says they should.

Example

import requests

r = requests.post(
    'https://api.inkspan.dev/v1/generate/html',
    headers={'X-API-Key': 'ink_live_...'},
    json={
        "html": "<h1>Invoice INV-1042</h1><p>Total: $61.00</p>"
    },
)
r.raise_for_status()
with open('document.pdf', 'wb') as f:
    f.write(r.content)

Request parameters

Name	Type	Required	Description
`html`	string	yes	The HTML document or fragment to render.
`filename`	string	no	Filename in the response's Content-Disposition. Defaults to `document.pdf`.

Response

Returns a PDF as a binary stream with Content-Type: application/pdf and Content-Disposition: attachment; filename=document.pdf. Write the response body straight to disk — do not parse it as JSON.

Things that catch people out

Relative URLs have no base to resolve against. Reference images and stylesheets with absolute https:// URLs, or inline them as data: URIs.
Page size and margins come from CSS, not from a parameter. Set @page { size: A4; margin: 18mm; } in your HTML to control them.
External resources are fetched server-side with SSRF protection, so private-network and file:// URLs are rejected. Host assets publicly or inline them.
Web fonts must be reachable over HTTPS. A font that 404s falls back silently rather than failing the request, which is the usual cause of 'the PDF looks wrong but returned 200'.

Errors

Status	Meaning	Fix
`401`	Invalid or missing API key	Send your key in the `X-API-Key` header.
`402`	Monthly quota exceeded	The response reports used/quota. Upgrade at inkspan.dev/#pricing.
`422`	Missing or invalid parameter	Check required fields in the table above — the body names the offending field.

Failed requests do not count against your quota; only successful ones are metered.

Frequently asked questions

Is there a free tier?

Yes — 100 documents a month, no card required. Usage-based plans start at $19/month when you outgrow it.

How do I authenticate?

Send your key in the X-API-Key header on every request.

Do failed requests count against my quota?

No. Only successful requests are metered.

Get a free API key →

Full guides for /v1/generate/html: cURL · Python · Node.js · all guides