Website Speed Test: How to Check Page Speed for Free

To check website speed, run a free page speed test: paste the URL into our page speed checker or Google PageSpeed Insights, test the mobile result first and then desktop. Look at two kinds of data. Field data shows how real visitors experienced the page over the last 28 days, and lab data is a single simulated load that helps explain why. Good means LCP of 2.5 seconds or less, INP of 200 ms or less and CLS of 0.1 or less.

Mobile and desktop are scored separately, and mobile is usually the weaker of the two because the test simulates a mid-range phone on a slower connection. Test one page of each template, not only the home page. Below we compare the free tools, explain how to run a fair test, and translate each number into plain English so you know what to fix.

Key takeaways

Paste a URL into PageSpeed Insights to see 28 days of real-visitor Core Web Vitals plus a simulated Lighthouse test.
Aim for LCP of 2.5 seconds or less, INP of 200 ms or less and CLS of 0.1 or less.
Trust field data for the verdict and lab data for the diagnosis, and run lab tests three times using the middle result.
Start with mobile LCP, as only 62% of sites had good LCP on mobile in the 2025 Web Almanac.

What is the quickest way to check page speed?

Open the free Make It Flow page speed checker and paste the full URL, including https://.
Read the mobile and desktop scores side by side. Both come from Google PageSpeed data, so they match what Google reports.
Check the real-user Core Web Vitals (LCP, INP and CLS) for the page and for the whole site, each rated good, needs improvement or poor.
Work through the top opportunities, which come with a plain-English fix for each.

If you want speed checked alongside SEO, security and email settings in one report, the website speed test is part of every free audit. You can see all audit features on the features page.

Which free tools can I use to test website speed?

Tool	Data type	Best for
Make It Flow page speed checker	Field (real users) and lab	Mobile and desktop results on one screen, with plain-English fixes
PageSpeed Insights	Field (real users) and lab	A quick, authoritative first check of any public page
Google Search Console, Core Web Vitals report	Field	Seeing which groups of pages on your own site fail
Lighthouse in Chrome DevTools	Lab	Testing pages behind a login or on a staging site
Chrome DevTools Network and Performance panels	Lab	Finding exactly which file or script is slow
WebPageTest	Lab	Testing from different locations and connection speeds, filmstrip views
GTmetrix	Lab	A second opinion with a waterfall chart

What is the difference between a page speed test and a website speed test?

A page speed test measures one URL. A website speed test is really a set of page tests, because every template on your site loads different images, scripts and fonts. Your home page can score well while product pages or blog posts are slow.

Most tools, including PageSpeed Insights and our page speed checker, test one page at a time. To judge the whole site, test one page of each template, then use Search Console's Core Web Vitals report, which groups similar pages together (more on that below).

What is the difference between field data and lab data?

Field data tells you whether there is a problem. Lab data helps you find out why. If they disagree, trust field data for the verdict and lab data for the diagnosis.

	Field data	Lab data
Where it comes from	The Chrome User Experience Report (CrUX): real Chrome users who share usage statistics	Lighthouse loading the page once on simulated hardware and network
Time covered	A rolling 28-day window	The moment you run the test
Core Web Vitals included	LCP, INP and CLS	LCP and CLS; Total Blocking Time stands in for INP
Best used for	Deciding whether real visitors have a problem	Diagnosing the cause and checking a fix straight away
Availability	Only for pages and sites with enough traffic	Any public URL

Google uses field data when it assesses page experience, so that is the number to aim at. Lab scores move from run to run and differ between tools: our GTmetrix vs PageSpeed Insights comparison explains why their scores differ.

Should I test website speed on mobile or desktop?

Both, but start with mobile. PageSpeed Insights reports field data and lab results for each device separately, and a page can pass on desktop while failing on mobile. Google's lab profile for mobile simulates a mid-range phone with a slowed CPU and network, so it exposes heavy images and scripts that a fast laptop hides. If most of your visitors are on desktop, which your analytics will show, give the desktop result more weight, but do not ignore either.

How do I check my website speed with PageSpeed Insights?

Go to PageSpeed Insights and enter the full URL, including https://.
Leave the Mobile tab selected first. For most sites mobile is where problems show, because the test simulates a mid-range phone on a slower connection.
Read the top section, "Discover what your real users are experiencing". This is field data from the Chrome User Experience Report (CrUX). If your page lacks enough traffic, PageSpeed Insights falls back to data for the whole origin, or shows nothing.
Scroll to "Diagnose performance issues". This is a Lighthouse lab run on a simulated mid-range phone with a throttled connection.
Note the Lighthouse version at the bottom of the report, so you compare like with like next time.

Test more than the home page. Run a product or service page, a blog post and your contact page, because templates often differ.

What do the numbers in a speed test mean?

Largest Contentful Paint (LCP)

When the biggest image or block of text in the viewport finished rendering. It is the closest single number to "when did the page look ready". Good is 2.5 seconds or less; poor is over 4 seconds.

Interaction to Next Paint (INP)

How long the page takes to respond visually after a tap, click or key press, across the whole visit. Good is 200 ms or less; poor is over 500 ms. It only appears in field data, because a lab test does not tap anything. Total Blocking Time in Lighthouse is the closest lab stand-in.

Cumulative Layout Shift (CLS)

How much content moves unexpectedly while the page loads. Good is 0.1 or less; poor is over 0.25. Images without dimensions, late-loading adverts and cookie banners are the usual causes.

First Contentful Paint (FCP)

When anything first appears on screen. Good is 1.8 seconds or less; poor is over 3 seconds.

Time to First Byte (TTFB)

How long the server takes to start sending the page. Good is 0.8 seconds or less; poor is over 1.8 seconds. A high TTFB points at hosting, caching or the database.

The performance score

The 0 to 100 score is a weighted blend of lab metrics. Google classes 90 to 100 as good, 50 to 89 as needs improvement and 0 to 49 as poor. It is a diagnostic, not a ranking factor in itself. See our guide to the PageSpeed Insights score for how it is calculated.

Why does my score change every time I test?

Lab tests run on shared infrastructure, over a network, against a server that may be busy. Small variations of a few points are normal. To get a fair picture:

Run each test three times and use the middle result.
Test at a similar time of day.
Do not compare a mobile result with a desktop one.
Check the Lighthouse version has not changed between runs.

Field data moves slowly because it is a rolling 28-day window. After a fix, expect up to four weeks before the field numbers fully reflect it.

How do I check speed for the whole site, not one page?

Use the Core Web Vitals report in Google Search Console. It groups similar URLs and labels each group good, needs improvement or poor for mobile and desktop separately. When you fix a template, use "Validate fix" to start Google's monitoring period.

For a crawl-based view, an audit tool that tests many pages at once is faster than running PageSpeed Insights URL by URL. Make It Flow includes PageSpeed and Core Web Vitals in every website speed test, and paid plans add a whole-site crawl.

How do I test page load speed like a real mobile visitor?

In Chrome DevTools, open the Network panel and choose a throttling preset such as "Slow 4G", and in the Performance panel set CPU throttling to 4x slowdown. That roughly matches the conditions Lighthouse simulates: 150 ms round-trip time, 1.6 Mbps download and a 4x CPU slowdown. Also tick "Disable cache" so you see a first visit.

Better still, borrow a mid-range Android phone, turn off Wi-Fi and load the site on mobile data. It is the quickest way to feel what customers feel.

Which number should I worry about most?

Start with LCP on mobile in field data. It is the metric sites fail most often and it reflects the first impression visitors get. In the 2025 Web Almanac, 62% of sites had good LCP on mobile, against 77% for INP and 81% for CLS. If your LCP is good, move on to INP, particularly if your site has menus, filters or forms.

What should I do after testing my website speed?

Fix the biggest problem first, then re-test on the same device type. The usual causes, in rough order of how often they come up:

A large hero image slowing LCP. Compress it, serve a modern format such as WebP or AVIF, and do not lazy-load the main image. Our guide to improving Largest Contentful Paint goes step by step.
Render-blocking CSS and JavaScript delaying the first paint. See how to eliminate render-blocking resources.
Slow server response (high TTFB). Page caching, a CDN or better hosting usually help most. See how to reduce TTFB.
Heavy third-party scripts such as chat widgets, tag managers and ad code hurting INP. Remove what you do not use and delay the rest.
Images and embeds without dimensions causing CLS. Set width and height, and reserve space for ads and banners.

On WordPress, our guide to speeding up a WordPress site covers plugins, caching and hosting. For what each metric means in depth, read Core Web Vitals explained.

Frequently asked questions

What is a good website speed?

For Google's Core Web Vitals, good means LCP of 2.5 seconds or less, INP of 200 ms or less and CLS of 0.1 or less, measured at the 75th percentile of real visits. A page passes when all three are good. The Lighthouse performance score is a separate lab number, where 90 to 100 counts as good.

Is there a free page speed test?

Yes. Google PageSpeed Insights is free, and our page speed checker uses the same Google data to show mobile and desktop results together with plain-English fixes. Lighthouse in Chrome DevTools is free too and works on pages behind a login.

Is PageSpeed Insights accurate?

The field data is real measurements from Chrome users who share usage statistics, so it is accurate for those visitors. It excludes Safari and Chrome on iOS, so iPhone users are missing. The lab data is a consistent simulation and useful for comparing before and after, but it will not match any one visitor exactly.

Why does PageSpeed Insights say "no data" for my site?

CrUX only reports pages and origins with enough eligible visitors, and Google does not publish the exact threshold. Smaller sites often have origin data but no page-level data, or none at all. Use the lab results and test regularly instead.

Can I test a website that is behind a login or on staging?

PageSpeed Insights needs a publicly reachable URL. Run Lighthouse from Chrome DevTools instead, where it tests whatever page you have open, including logged-in pages and local or staging sites.

What internet speed should I test on?

Test on a throttled connection that represents your typical visitor, not your fast office connection. Lighthouse's default mobile profile is a sensible baseline. If you know your audience is rural or on older phones, test slower still.

Do website speed checker tools slow down my site?

A single test is one page load, which is negligible for any normal hosting. Very frequent automated testing of many pages can add load, so schedule bulk checks outside peak hours if your server is small.

What to do next

Test your three most important pages on mobile, write down LCP, INP, CLS and TTFB, and save the reports. That gives you a baseline to measure every change against. Use the free page speed checker for a quick check of any page, the Make It Flow website speed test to record results over time, or run a free website audit to check speed alongside SEO and security in one go.