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Top 13 Website Speed Testing Tools in 2025

Updated on: March 12, 2025

Table of contents

There are a lot of reasons why people choose to shop at one online store over another or pick one streaming service over another from the type of service they are getting to pricing, quality and, you’ve guessed it from the title, speed. The speed to which I’m referring is the speed at which the website loads and reacts to user input. In one of my previous articles about network latency, I talked about how big of a difference even a two-second extra delay makes.

In this article, I will go over some of the speed testing basics like the metrics you need to watch out for and the tools you’ll need to test and track speed issues and performance. The list will include the best website testing tools that are both free and paid and I’ll be sure to mention which is which.

Why Should You Use Website Speed Testing Tools

I believe it’s important to understand exactly how speed testing can help you in delivering a better user experience so I figured I’d come up with a list of the most common website performance metrics to measure for and issues to watch out for.

  • Resources that take too long to load. These can be anything from Fonts and Images to different plugins and JS files that slow down the loading of your website.
  • TTB and FMP. Time to first byte and the First meaningful paint are two essential metrics that you need to pay attention to. They will show you when your website starts loading and the second it starts displaying information.
  • Load time, number of requests, and page sizes. You’ll want to keep an eye on these as they can dramatically increase the load time of your website.
  • HTTP headers. HTTP headers is how servers communicate with the server by sending information back and forward via a request or response. You’ll need to test these responses and requests to make sure you are getting and sending the right message between the two. This also comes in handy when you are trying to debug different errors you might have.

Website Speed 101: Basic Concepts to Get Started

Before we dive into the list of tools we’ll use to optimize our website, I think we should take a second look at the basic concepts behind website speed optimization.

Big load times

One of the most important aspects of website optimization is the speed at which your website loads. There are lots of reasons why your website is loading slowly and one of them is your server. Measuring your time to first byte will let you know if you have an issue with the response time of your server and if that’s the case then I might suggest you look towards a CDN to help you solve this particular problem.

Render-blocking code

Another reason why your website loads slowly is that you have code that blocks the rendering of your website. This could be Javascript, CSS, or any other type of code that might block the rendering of the current webpage. This is one place you can’t afford to cut corners as it will directly impact the experience your users have on your website.

There are several ways to defer render-blocking code and I’m going to cover the top two scenarios: Javascript and CSS.

For JavaScript, we can run a little script that will defer the scripts that would otherwise block the rendering of our pages. Here’s a little example:

<script>
function deferLoadingTheCode() {
    var element = document.createElement("script");
    element.src = "delayTheCode.js";
    document.body.appendChild(element);
}
window.addEventListener("load", deferLoadingTheCode, false);
</script>

All you need to do is drop this somewhere in your <head> tag of your HTML and you should be good to go.

The next part to tackle is CSS. With your CSS the goal is to get it as small as possible and there are two ways to do it, one would be to remove all the unnecessary classes and either remove them altogether or move them to a different CSS file that can be loaded on other pages or after the critical content of the page has loaded.

The second thing you could do is minify your CSS file. This is a process where you take the unnecessary characters from your files that would otherwise take up space, thus taking longer to load. Minifying doesn’t only apply to CSS, you can also remove unnecessary characters from JavaScript and HTML too. The characters I’m referring to as unnecessary are whitespace characters (the spacebar and the enter key), comments, and block delimiters. Most often than not, developers use a piece of software to get this done.

HTTP Requests

The next thing to look for is your HTTP requests. Every time you load a website, there are a series of requests being made to the servers. Every request will have a response and each server will have a set number of concurrent requests it can handle. The more requests you have, the more requests your server will have to deal with, and the longer it will take to respond.

These requests can be hard to track and more often than not, the number of requests fluctuates up and down, especially if you are working with any third-party services. To measure and keep track of these requests, you’ll want to use a synthetic monitoring service like Sematext Synthetics. With a simple setup, you can track the overall number of requests, load time, responses, and much more. We’ll talk more about Sematext Synthetics in a second.

But it’s time to get to the main event. The reason why you are here in the first place is the top website speed testing tools you can use right now. Without further ado, let’s jump right in.

The 13 Best Website Speed Testing Tools

Now that you have the basics of website speed testing, here are some of the best tools to help you test page load and improve website performance.

1. Sematext Synthetics

website performance test tools

Sematext Synthetics has quickly become a favorite amongst our users. It’s reliable and simple to use despite being feature-rich. You can monitor API and website speed and uptime from multiple locations across the globe, measure performance across devices and browsers, and identify issues with third-party resources, SSL certificates, and a lot more. Sematext uses Playwright to simulate user journeys through one or more web pages or even multiple websites so that you can set up some really interesting monitoring scenarios. Oh, and you can generate these scripts using AI. Everything you monitor with Sematext Synthetics can be exposed via  Status Pages. The Incidents feature allows you to share the status of any incidents, any scheduled maintenance windows, or downtimes.

Getting started is dead simple. Just enter a URL, pick one or more locations and monitoring will start immediately. You can always add more locations, including Private Locations, change success/failure conditions, how you get notified about failures, etc.

Key Features: 

  • Multiple from monitoring locations
  • Support for private locations for monitoring internal websites and APIs
  • SSL monitoring: expiration, validity, certificate authority (CA)
  • API monitoring with the ability to extract API response data, chart it, and alert on it
  • Website monitoring with page waterfall charts, core web vitals, ability to monitor page context, extract numerical data, chart and alert on it
  • User journey scripts for simulating user actions, including support to store passwords and the like securely. Ability to sync scripts with GitHub
  • Simulating different types of devices, such as mobile, tablet, and desktop
  • CI/CD integration for running a group of monitors as part of continuous integration to avoid deploying regressions to production
  • Status pages, both private and public, customizable, including the ability to host them at a custom domain. Ability to publish and update incidents on status pages, including scheduled maintenance windows.
  • Correlation of synthetic checks with backend performance metrics, logs, and traces
  • Support for accessing protected APIs and pages using several authentication methods.

Pros: 

  • Easy to use and get started. Literally in 5 minutes.
  • Cost-friendly Pay As You Go plan, ability to change plans at any time, and without speaking with anyone
  • Comprehensive feature set
  • Ability to monitor end-to-end by drilling from failed synthetic monitor runs into metrics, logs, or traces for backend applications and databases
  • Numerous alert notifications available, from email to Slack to webhooks to SMS
  • Great customer support and the ability to easily get custom plans
  • Granular insights into resource performance (e.g., unoptimized images or render-blocking scripts)
  • Multiple monitoring locations, including Private Locations
  • Full-stack observability

Cons: 

  • No out of the box SLA/SLO charts (they are in progress)
  • no free tier beyond the 14-day trial.

Pricing: 

  • Starts at $2 per HTTP monitor and $7 per browser monitor

2. Pingdom Speed Test

website performance testing tool

Pingdom is another well-known website speed test tool that’s been around for ages. It requires no login to use and the reports are less detailed than what you’d get from Google PageSpeed Insights. The site’s performance is graded from 0 to 100 and then has a breakdown of the response codes, content size, request types, requests by domain, and a waterfall chart that lets you see details on your file load times.

Their free tool allows you to run a single test from any of their 70 locations, and if you sign up to their Synthetics solution, which starts at $10/month for 10 uptime checks, you can set up page speed monitoring as well as alerting.

Key Features: 

  • Geographic testing across seven global nodes
  • performance grading (A–F)
  • HTTP request analysis. 

Pros: 

  • Intuitive interface ideal for non-technical users
  • No login required for basic speed test
  • actionable recommendations (e.g., “Enable compression”)
  • integration with SolarWinds ecosystem – RUM, infra, logs, and APM 

Cons: 

  • Limited API access in free plans
  • No support for custom network throttling

Pricing: 

  • Free: up to 3 basic tests per day 
  • Paid: Starts at $15/month ($10/month annually) for 10 Uptime, 1 advanced checks and 50 SMS alerts

Want to see how Sematext stacks up? Check out our page on Sematext vs Pingdom.

3. Google PageSpeed Insights

website performance test tools

For years Google PageSpeed Insights has been the go-to tool for testing and grading your website. It’s a simple tool created by Google that benchmarks websites and grades them on a scale of 1 to 100 for both mobile and desktop. 

The higher the number, the faster the website is.

While Google PageSpeed Insights has been the go-to tool for testing and grading your website for years, it’s important to understand its strengths and limitations.

Key Features:

  • Simple UI
  • Performance grading (1-100 for mobile and desktop)
  • Core Web Vitals tracking
  • Mobile/desktop prioritization
  • Detailed analysis (render-blocking code, TTFB, page sizes)
  • Actionable recommendations
  • Controlled testing environment

Pros:

  • User-friendly
  • Comprehensive insights
  • Optimized recommendations
  • Direct alignment with Google’s SEO ranking factors
  • No cost involved
  • Clear prioritization of fixes

Cons:

  • Lacks customization
  • Field data excludes iOS Chrome users
  • Lab simulations may misrepresent real-world conditions
  • No alerting system
  • No multi-location testing

Pricing: 

  • Free to use

4. Uptrends

website performance testing

Uptrends offers a straightforward test and you can configure the test to run either from a mobile device or a desktop. For the desktop test, you can also pick the resolution of the screen from one of four browsers (Chrome, Firefox, PhantomJS, and IE) and bandwidth throttling to test the site under different speed scenarios.

Uptrends distinguishes itself with cross-browser testing, measuring performance on Chrome, Firefox, and Safari across desktop and mobile4. It’s Web Vitals monitoring tracks LCP, CLS, and First Input Delay (FID), with alerts triggered by thresholds like LCP > 2.5 seconds. 

The tool’s real Android device testing provides accurate mobile insights, bypassing emulation inaccuracies.

Key Features: 

  • Cross-browser testing (Chrome, Firefox, Safari)
  • Bandwidth throttling
  • Real Android device monitoring
  • Web Vitals thresholds
  • Integration with many incident management channels 

Pros: 

  • Accurate mobile performance insights via physical devices
  • Performance testing from 230 locations
  • Detailed render-time comparisons
  • Website & performance monitoring
  • Full-stack observability

Cons: 

Pricing: 

  • Browser monitoring starts at $13.68/credit/month
  • Uptime and Availability Monitoring starts at $5.10/ credit/month
  • Real User Monitoring starts at $8.91/ month

See Sematext vs. Uptrends to see how we stack up.

5. WebPageTest

best website speed test

WebPageTest.org is an open-source website performance testing tool that allows you to benchmark your website from one of its 40 locations and a wide range of devices. You can also choose to simulate your tests over a slow mobile network or a fast 4G network. The result will be graded from F to A and will include information on compression, TTFB, caching, waterfall charts for the resources load speed, and more.

It also features a rather special test where they run a test 3 times and display all three data sets. This helps figure out if the DNS or CDN might cause any delay and if the server can respond to all requests.

Key Features: 

  • Custom network throttling
  • device emulation (e.g., Moto G4)
  • filmstrip rendering analysis
  • private instance hosting

Pros: 

  • Unparalleled customization for replicating user environments
  • open-source flexibility
  • ilmstrip views to detect layout shifts

Cons: 

  • Steep learning curve for beginners
  • inconsistent results due to shared infrastructure
  • no built-in alerting

Pricing:

  • Free to use

6. GTmetrix

website performance tool

GTmetrix allows you to get detailed information on your page speed, timings, performance score, and much more. GTmetrix also provides information about how to fix the issues that were exposed by the test.

Without registering, you can only run a test from one location, Vancouver, Canada, but after you sign up for a free account, you’ll get to choose your location, different browsers, and even the connection type. 

This should paint a better picture of how your website works in different scenarios.

Key Features: 

  • Lighthouse and PageSpeed integration
  • video capture of page loads
  • server-specific recommendations (e.g., PHP upgrades) 

Pros: 

  • Free tier with basic audits
  • Global CDN performance insights
  • Ad-blocking simulations for cleaner metrics 

Cons: 

  • Redundant features with Google PSI
  • advanced tools locked behind higher paying plans
  • limited RUM capabilities

Pricing: 

  • Free plan available for a few basic audits
  • Paid plans start at $5/month for 1 monitored slot, scale up to $600 depending on # of monitored slots, and additional features

7. dotcom-monitor

website performance testing tools

With Dotcom-monitor, you get 25 different locations and 7 different browsers that include Blackberry, which should make me think they really need to update their service, or perhaps they are historians.

After you run the test, you’ll get graded based on your load time and get details on your server responses. You’ll also be able to check what a repeat visit looks like for someone who comes to your website a second time and has already cached resources on their machine. You’ll also get a detailed page speed insight report generated by Lighthouse.

Key Features: 

  • Real-browser monitoring
  • Extensive browser support
  • Capture page load videos
  • Detailed web performance monitoring metrics
  • API endpoint validation
  • Transaction monitoring
  • Alerting capabilities

Pros: 

  • Authentic Chrome/Firefox testing environments
  • Scalable for enterprises
  • Detailed waterfall charts
  • Customizable reports 
  • Full-stack observability (lacks log monitoring capabilities)
  • 30-day free trial available

Cons: 

  • High starting price – stacks up easily
  • Occasional server latency issues
  • No mobile-device testing

Pricing: 

  • Page performance starts at $29.96/mo
  • Website and API starts at $20/mo

8. Site 24×7

website speed test tools

Site24x7 employs real Firefox browsers for testing, capturing JavaScript execution and third-party script impacts. The tool’s waterfall charts highlight sequential vs. parallel resource loading, aiding in dependency optimization. 

However, limited documentation on mobile testing and lack of Web Vitals integration reduce its appeal compared to Uptrends or Sematext

Site24x7 is a simple product that offers a free alternative to Pingdom. Their “Free Forever plan” offers 5 monitors with email notification, which is probably enough for any small website.

Key Features: 

  • Real Firefox browser testing
  • dependency mapping via waterfall charts
  • infrastructure monitoring
  • Full-stack observability 

Pros: 

  • Identifies third-party script impacts
  • Affordable pricing for SMBs
  • Integration with Zoho ecosystem 

Cons: 

  • No Web Vitals tracking
  • Limited mobile-testing documentation
  • Steep pricing for small businesses
  • Some users reported that editing user settings can be cumbersome
  • Accepts only annual payments
  • Clunky UI navigation.

Pricing:

  • “Forever free plan” available
  • Paid plans start at $9/month, but to get a somewhat comprehensive featureset, the $35/mo plan is required

Want to see how Sematext stacks up? Check out our page on Sematext vs Site24x7.

9. Uptime

website load time testing

Uptime.com has emerged as a versatile website monitoring platform, combining global performance tracking with real-user insights to optimize digital experiences. Following its 2023 launch of Page Speed Monitoring1, the tool now integrates synthetic checks, transaction simulations, and multi-location testing, positioning itself as a robust solution for enterprises prioritizing uptime and speed optimization.

Key features:

  • Audit metrics like Time to Interactive (TTI) and First Contentful Paint (FCP)
  • Daily reports with actionable recommendations 
  • 121 global probe locations across 50+ countries
  • Synthetic transaction checks simulate user interactions like form submissions and checkout flows
  • Real-user monitoring
  • Customizable checks with SLA targets and alerts
  • Waterfall charts to analyze resource-load sequences
  • Historical performance data

Pros:

  • Intuitive UI
  • Granular alert system
  • Integrations with DevOps tools like PagerDuty and Opsgenie
  • 14-day free trial available
  • Multi-location testing

Cons:

  • Pricing model limits the Starter plan ($20/month) to only 30 uptime checks, forcing large-scale users into costly Enterprise tiers
  • Occasional false alarms
  • Mobile app lacks check-creation capabilities
  • Steep learning curve complicates advanced configurations

Pricing: 

  • Starts at $30/mo ($20/mo when paid annually) for 30 basic checks, 1 page speed check with 3 locations per check, 5 min check frequency, and 50k RUM page views

10. Geekflare Website Audit

website performance testing tool

Powered by Google Lighthouse, Geekflare Website Audit is a simple website speed test that provides basic actionable information about your website. Besides data like TTFB, SEO score, performance score, and others, you get a series of snapshots of your website loading.

A great feature of the Geekflare Website audit is its request waterfall chart that allows you to see how your resources are being requested and loaded. This chart could decide to defer the loading of different resources to get the First meaningful paint number down as much as possible.

Key Features

  • Desktop and mobile testing
  • Provides a comprehensive breakdown of key metrics, including IP address, test time and location, performance score, best practices score, SEO score, accessibility score
  • Check Core Web Vitals performance

Pros

  • Evaluates essential aspects such as SEO performance, security vulnerabilities, and performance optimization
  • User-friendly UI
  • Offers specific recommendations to improve website health

Cons

  • Limited integrations with certain external tools
  • Some advanced functionalities might necessitate the use of third-party solutions

Pricing: 

  • Free to use

11. Yellow Lab Tools

website speed optimization tools

Yellow Lab Tools is a newer addition to the website monitoring scene and provides basic information about your website without beating around the bush. 

The first thing you see once you run the test is a grade with a score followed by the test details that include the page weight with all the details related to it, request details, DOM details, bottlenecks, CSS details, and server configuration details. 

All in all, it is a great tool, but it does seem like it lacks in-depth information, especially when you compare it with the other tools in this list.

Key Features: 

  • Code complexity analysis
  • JavaScript error detection
  • Server configuration audits

Pros: 

  • Identifies DOM clutter and memory leaks
  • open-source integration

Cons: 

  • No performance timing metrics
  • Limited documentation
  • Technical implementation
  • False positives in error reporting

Pricing: 

  • Free to use

12. Web Page Analyzer

WebsiteOptimization.com‘s speed checker, active since 2003, is a pioneering tool for website performance analysis. It conducts an in-depth evaluation of webpages, examining their size, individual components like images and code, and loading times. The tool breaks down pages into elements, identifying bottlenecks and providing clear recommendations for optimization.

By measuring load times of specific resources, it pinpoints areas for improvement. With its longevity and adaptability, the speed checker offers practical advice aligned with evolving web standards, enabling website owners to enhance user experience and search engine rankings through targeted optimizations for faster loading speeds.

Key Features: 

  • Page size breakdowns
  • HTTP request counts
  • cost estimation for bandwidth

Pros: 

  • Free and no signup required
  • historical data comparison 

Cons: 

  • Outdated interface
  • Lacks modern metrics like LCP
  • No actionable recommendations

Pricing: 

  • Free to use

13. Google Chrome DevTools

website performance test tools

If you are developing your website with Chrome, then most likely you are already familiar with it. Chrome DevTools is a simple tool that lets you see a waterfall timeline with all your resources and details on what’s costing you precious load time.

To access it you need to have Chrome installed (dooh) and then you open it up by pressing F12 if you are on a Windows machine or CMD + Option + I if you are using a MAC.

There’s no alerting, no fancy location-picking options, but it’s free and comes with your browser, and requires no login or registration whatsoever.

Key features: 

  • Network throttling
  • CPU throttling
  • Lighthouse audits
  • memory profiling

Pros: 

  • Built-in browser tool for debugging
  • Real-time performance metrics

Cons: 

  • Requires manual execution for each test
  • No automated monitoring
  • Steep learning curve for non-developers

Pricing: 

  • Free to use

Final thoughts

As you can see, there are a lot of options to choose from, each with its unique feature, and it’s up to you to test them and figure out which one works best for you. I think it’s worth noting that speed testing is something you should be doing long after you’ve finished developing the website. If you’re new to this, read our tutorial on how to measure website speed the right way.

Over time, things will change, especially if you are using third-party APIs and you’ll want to be one step ahead of them. Using a site speed testing service or a website monitoring tool is the best way to meet and tackle challenges, improve website performance, and deliver the best experience to your users. Sematext Synthetics can help you on that journey. Give it a try! There’s a 14-day free trial available to test out all its capabilities.

If you’re looking for ways to speed up your WordPress website specifically, then be sure to check out this short video below. We go over all the tips and tricks you need to make sure your WordPress website is running like clockwork.

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