PageSpeed Insights¶
FAT Agent can integrate with Google's PageSpeed Insights API as an alternative to local Lighthouse runs. This is useful in CI environments where installing Chrome is impractical.
Usage¶
When running an audit, FAT Agent can use PageSpeed Insights if configured:
Or from the analysis pipeline, Lighthouse results can be supplemented with PSI data.
API Access¶
PageSpeed Insights API is free with rate limits. For higher throughput, provide a Google API key:
What It Provides¶
| Metric | Description |
|---|---|
| Performance Score | Overall Lighthouse performance score (0--100) |
| FCP | First Contentful Paint |
| LCP | Largest Contentful Paint |
| TBT | Total Blocking Time |
| CLS | Cumulative Layout Shift |
| Speed Index | How quickly content is visually displayed |
Differences from Local Lighthouse¶
| Aspect | Local Lighthouse | PageSpeed Insights |
|---|---|---|
| Network | Your connection | Google's servers |
| Consistency | Varies by machine | Consistent infrastructure |
| Throttling | Configurable | Fixed presets |
| Real User Data | No | Yes (CrUX data when available) |
| Rate Limits | None | 25,000/day free |
When to Use¶
- CI/CD pipelines where installing Chrome is difficult
- Remote audits where you want consistent network conditions
- CrUX data when you need real-user performance data
- Quick checks without local Lighthouse setup