SEO Score API vs PageSpeed Insights
Google's free hosted Lighthouse with real-user (CrUX) field data · Pricing: Free
PageSpeed Insights and SEO Score API both touch SEO, but they are different shapes of product. PageSpeed Insights is a Web tool + REST API (free, throttled); SEO Score API is a hosted REST API that returns a scored audit as JSON in seconds. This page is an honest side-by-side — including when you should pick PageSpeed Insights over us. Still shopping around? See our roundup of PageSpeed Insights alternatives organized by use case.
Side-by-side
| Feature | PageSpeed Insights | SEO Score API |
|---|---|---|
| Pricing | Free | $0 free, $5+ / mo |
| Focus | Performance + Web Vitals | SEO + AI readability + performance |
| Real-user (CrUX) data | Yes | On request (cwv=true) |
| AI readability score | No | Yes |
| SXO / AEO / AIO scores | No | Yes (Starter+) |
| API quotas | 25k/day shared, ~400/100s key | Per-plan, dedicated |
| Per-key auth | Optional | Required (X-API-Key) |
| Output | JSON (Lighthouse + CrUX) | Compact scored JSON with priorities |
| CI/CD examples | Build your own | Official GitHub Action |
| Schema / structured-data checks | Limited | Detailed |
When each tool wins
Pick PageSpeed Insights when…
- You want Google's own opinion of a page's Core Web Vitals — including real-user data from CrUX.
- You only need a quick check on a few URLs occasionally.
- You're optimizing for Google's specific page-experience signals.
Pick SEO Score API when…
- You want broader SEO and AI-readiness checks beyond performance.
- You audit at higher volume than PSI's free quota allows (25k requests/day shared globally).
- You want a single API for SEO + AI readability + SXO/AEO/AIO scoring, not just Web Vitals.
PageSpeed Insights alternatives, by use case
Not sure an audit API is the right swap? Here are the strongest PageSpeed Insights alternatives and PageSpeed Insights competitors, grouped by what you actually need — so you pick on use case, not marketing budget.
If you want broader SEO checks (not just performance)
- SEO Score API. 80+ checks: SEO + perf + a11y + AI readability + SXO/AEO/AIO. Hosted API. — learn more
- Ahrefs Site Audit. Scheduled crawls inside the $129+/mo Ahrefs plan.
If you want raw Lighthouse without PSI's quota
- Lighthouse CLI. Run it yourself, no quota — but you supply the runner.
- Lighthouse CI. Self-hosted, free, designed for build pipelines.
If you want real-user monitoring
- Chrome UX Report (CrUX) BigQuery. Free, raw RUM data straight from Google.
- SpeedCurve / Calibre. Paid synthetic + real-user monitoring suites.
Frequently asked
Does SEO Score API replace PageSpeed Insights?
Only partly. We include performance signals and, on request (cwv=true), the Core Web Vitals PSI measures, but not the full Lighthouse trace. For a full performance breakdown, keep using PSI. For broader SEO + AI readiness checks across many URLs, use us.
Why use a paid tool when PSI is free?
PSI is free and excellent for spot checks. At higher volume you hit quotas (25k/day shared globally, ~400 requests per 100s per key) and you'd build the rest of the stack yourself: batch, history, alerts, scoring layer, broader SEO depth. SEO Score API covers that out of the box.
Can I get Core Web Vitals from SEO Score API?
Yes, on request. Add cwv=true to an audit and the response includes LCP, INP, CLS, FCP and TTFB as measured by PageSpeed Insights, with real-user data where Google has it. It is off by default because it takes about 10 seconds longer. Every audit also reports response time, HTML size, DOM size and render-path basics.
Does SEO Score API check schema and structured data?
Yes — every audit checks JSON-LD presence, validates types, and reports gaps. PSI's structured-data coverage is comparatively shallow.
Audit your site free — no PageSpeed Insights subscription, no credit card.
Score any URL across 80+ checks in one API call. Free tier, key in seconds.