Web fonts in generated PDFs: why they fall back, and how to make them load

The PDF shows Times where the page showed your brand font. Causes — timing, CORS, formats, licensing — and the fix for each.

Updated 31 August 2026

A PDF that renders in the wrong font is the most common quality complaint in document generation. The page looked right in the browser; the file looks like 1998. Here is why.

Timing

Chromium starts the PDF the moment you ask. If the font is still downloading, the text is laid out in the fallback and that is what gets printed. Fix: wait for the network to go idle before rendering (PDFGeny does this by default), or in your own Playwright code call `await page.evaluate(() => document.fonts.ready)`.

CORS

Fonts are subject to cross-origin rules. A font served from a CDN without `Access-Control-Allow-Origin` loads fine in the page where it is hosted and fails when the renderer fetches your HTML from another origin. Fix: serve fonts from the same host as the HTML, or add the header on the font host.

Format

WOFF2 is supported by every modern renderer. Old `.eot` and `.svg` font formats are not, and a stylesheet that lists them first can still resolve — but a stylesheet that lists only them will fall back. Ship WOFF2 with WOFF as a fallback and nothing else.

Inline HTML has no base URL

When you POST raw HTML, relative URLs like `/fonts/brand.woff2` have nothing to resolve against. Use absolute URLs, or embed the font as a data URI in an `@font-face` rule — for one or two weights the size is acceptable and the render is fully self-contained.

System fonts on the render server

If your CSS says `font-family: "Segoe UI", sans-serif` and the server is Linux, there is no Segoe UI. The fallback is whatever fontconfig picks, often DejaVu Sans. Either ship the font as a web font, or specify a fallback you actually like (Liberation Sans is metric-compatible with Arial).

Licensing

Most commercial font licences distinguish web use from "document embedding". Generating PDFs embeds the font in the file. Check the licence; open fonts (Inter, IBM Plex, Source Sans) avoid the question.

A checklist

• WOFF2 + WOFF, absolute or data URIs
• Fonts on the same origin as the HTML, or CORS headers set
• Wait for fonts before rendering
• A fallback stack that looks acceptable on Linux
• Licence permits embedding

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