> ## Documentation Index
> Fetch the complete documentation index at: https://pdfbase.dev/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Chromium Version

> PDFBase pins its Chromium version and gives 30 days' notice before upgrades.

## Why we pin

The #1 reason developers rage-quit PDF tools: "it looked fine yesterday, today the layout broke." Silent browser updates change rendering behavior — margins shift, fonts substitute differently, flexbox gaps change by a pixel.

PDFBase pins a specific Chromium version across all rendering infrastructure. Your PDFs render identically today, next week, and next month.

## Current version

| Component | Version | Pinned since |
| --------- | ------- | ------------ |
| Chromium  | —       | —            |
| Puppeteer | —       | —            |

<Note>
  Versions will be populated at launch and updated with each upgrade.
</Note>

## Upgrade policy

1. **30-day advance notice.** We announce the upcoming Chromium version via email, changelog, and the dashboard banner.
2. **Test environment first.** The new version is available on test keys (`pk_test_`) for the full 30-day notice period. Run your templates against it before the live cutover.
3. **Version header.** Every PDF response includes an `X-Chromium-Version` header so you can verify which version rendered your document.
4. **No surprise changes.** We never auto-upgrade Chromium without the notice period. If a critical security patch requires an emergency update, we'll communicate the timeline and scope.

## Checking your render version

Every response includes the Chromium version used:

```
X-Chromium-Version: 125.0.6422.60
```

With `debug: true`, the full version info appears in the debug output:

```json theme={null}
{
  "debug": {
    "chromium_version": "125.0.6422.60",
    "puppeteer_version": "22.8.0",
    ...
  }
}
```

## Why this matters

CSS rendering is not deterministic across Chromium versions. Known differences between versions include:

* Subpixel rounding in flexbox/grid layouts
* Font shaping and kerning behavior
* Default margin/padding on HTML elements
* SVG rendering precision
* `page-break` heuristics

Pinning eliminates all of these as variables. If your PDF looks right today, it looks right until the next announced upgrade — and you get 30 days to verify.