Free Website Speed Test

What this speed test measures

When you run a website speed test on RateMySite.io, we trigger a full Google Lighthouse audit on both mobile and desktop. That gives us four scores out of 100:

• Performance — how fast the page loads and becomes interactive
• SEO — whether the page follows search engine best practices
• Accessibility — how usable the page is for people with disabilities
• Best Practices — modern web standards (HTTPS, security headers, etc.)

We then convert those scores into a single overall letter grade from A+ to F.

Why website speed matters

Page speed directly affects three things every site owner cares about:

1. Conversion rate. Google research shows the probability of a bounce increases 32% when load time goes from 1s to 3s, and 90% when it goes from 1s to 5s.
2. Search rankings. Core Web Vitals are a confirmed Google ranking factor. Faster sites rank better.
3. Revenue. Amazon famously calculated that every 100ms of latency cost them 1% in sales. The same math applies to every e-commerce site.

What we test

A speed test on RateMySite.io measures the same six Core Web Vitals that Google uses:

• LCP — Largest Contentful Paint. When the biggest element on the page becomes visible.
• CLS — Cumulative Layout Shift. How much the page jumps around as it loads.
• INP — Interaction to Next Paint. How quickly the page responds to clicks and taps.
• FCP — First Contentful Paint. When the first text or image appears.
• Speed Index — How quickly the visible portion of the page is populated.
• TBT — Total Blocking Time. How long the main thread is blocked from responding to user input.

How to interpret your results

Don't panic over a single low number. Focus on the High Priority improvement checklist in your report — those are the changes that will move your score the most.

The most common wins are almost always the same:

• Compress and properly size images
• Eliminate render-blocking JavaScript and CSS
• Use a CDN to reduce server response time
• Defer or remove third-party scripts you don't need

Run your speed test now

Paste any URL into the box below. Within 30 seconds you'll have a complete report, a permanent shareable link, and a prioritized list of exactly what to fix first.