sitespeed.io vs Yellow Lab Tools (2026): which should you pick?
As of Oct 23, 2026, Yellow Lab Tools grades higher than sitespeed.io: 3.2 against 2.6 out of 4.0.
Checked Oct 23, 2026 · graded Oct 23, 2026 by ToolGPA
Yellow Lab Tools grades higher on ease of use and platforms. They get the same grade on value for money, the free plan and features.
Price, platforms and features side by side. The table says where each price was read and when.
sitespeed.io
Free open-source toolkit for testing and monitoring web performance
Free
Yellow Lab Tools
Free open-source audit of a page's speed and front-end code
Free
Which one is for you
Pick sitespeed.io if
- Fits if you're a developer who wants synthetic performance tests with no license cost
- Works for teams building their own performance dashboards in Grafana
Look elsewhere if
- Skip it if you don't use a command line, as there's no hosted service or account
- Watch out: ongoing monitoring needs your own server and storage, around $500 a year by the project's estimate
- Not for you if you need a vendor behind it, as the project says one core member maintains it in their free time
- Too light for real-user monitoring, which only comes in as CrUX data through a plugin
Pick Yellow Lab Tools if
- Fits if you're a front-end developer tracing what makes one page heavy or slow
- Works for testing pages on localhost or an intranet through a private copy
Look elsewhere if
- Skip it if you need a whole site checked, as each run tests one page address
- Not for you if you want ongoing monitoring, since no scheduled tests are described
- Watch out: the public site processes one run at a time, so a test can wait behind others
- Tight if you self-host on Windows, which the author says is untested; Linux and macOS are documented
- Watch out: under GPL-2.0, changes to a hosted copy's code must be published under the same license
How we grade them
| 2.6GPAsitespeed.ioGood | 3.2GPAYellow Lab ToolsVery good | |
|---|---|---|
| Value for money | AFree and open source, with nothing to sign up for, and it runs on your own computer through Docker or npm. Scheduled monitoring needs a server and storage, which the project puts at around $500 a year. | AFree under the GPL-2.0 license: the public website, its REST API, the npm command-line tool and the server code. There's no paid plan; the author takes donations through GitHub or Ko-fi. |
| Free plan and trial | AEntirely free, with every feature included and no account. The only costs are the machine you run it on and storage for results. | AEvery part is free, with no paid tier on record. The catch is the public instance, which processes one run at a time, so a test can wait in a queue. |
| Features | CHTML reports with Core Web Vitals, video, HAR waterfall and advice, tests in real browsers and on phones, scripted journeys, CI budgets and Grafana dashboards. It covers synthetic speed testing fully, a smaller job than technical SEO, and real-user figures only come through a CrUX plugin. | CA score out of 100 and a grade per rule across network, images, DOM, JavaScript, CSS, fonts and server config, with the offending files listed. It does a one-page front-end audit fully, but that's a smaller job, with no site-wide crawl or monitoring described. |
| Ease of use | DA command-line tool run through Docker or npm, and monitoring means setting up Graphite or InfluxDB with Grafana on your own server. No hosted version. | BNo rating on record. On the public site you give it a page address and a device type and wait for the report. Running your own copy is another matter: it needs Node.js, documented for Linux and macOS only. |
| Platforms and integrations | CRuns on Mac, Windows and Linux, with Grafana, Graphite, InfluxDB, S3, Google Cloud Storage, GitHub Actions, Jenkins and Slack. It's a program for computers only, with no hosted or phone version. | BWeb, with a public REST API that returns JSON, plus an npm command-line tool and a server you can run on Mac or Linux. No phone app, and no integrations on record. |
| Best for | free speed tests you run yourself | auditing one page's front-end code for free |
The GPA is the average of the five grades: an A is 4 points, an F is none. The full reasons are on each tool's page: sitespeed.io and Yellow Lab Tools. How we grade
Price against what you get
sitespeed.io has no paid plan and scores 1.7 out of 4 on features, ease of use and platforms. Yellow Lab Tools has no paid plan and scores 2.7.
Yellow Lab Tools scores higher for the same starting price. Of the other technical SEO tools on the chart, none scores higher than sitespeed.io for less, and none scores higher than Yellow Lab Tools for less.
Features, ease of use and platforms, averaged
What paid plans start at, a month (each step along is roughly double) →
- The best score at each price
- Has a free plan
- No free plan
Where they differ
In commonFree planmacOSLinuxOpen sourceSelf-hostablePage speed
At a glance
| sitespeed.io | Yellow Lab Tools | |
|---|---|---|
| Pricing | Free | Free |
| Starts at | Free | Free |
| Free plan | Entirely free and open source with nothing to sign up for. The only costs are the server you run it on and storage for results. | Entirely free: the public website, the API, the command-line tool and the self-hosted server, with donations through GitHub or Ko-fi. |
| Free trial | None listed | None listed |
| Web | ||
| macOS | ||
| Windows | ||
| Linux | ||
| Made by | sitespeed.io | Gaël Métais |
| Price read from | sitespeed.io | yellowlab.tools |
| Checked | Oct 23, 2026 | Oct 23, 2026 |
Worth knowing
sitespeed.io
- It is a command-line tool that you install and host yourself; there is no hosted service or account to sign up for.
- Ongoing monitoring needs your own server and storage, which the project estimates at around $500 a year.
- The project says it is maintained by one core member in their free time.
Yellow Lab Tools
- Each run tests one page address; the documentation describes no site-wide crawl or scheduled monitoring.
- The public instance queues runs and processes one at a time, so a test can wait behind others.
- Self-hosting needs Node.js and is documented for Linux and macOS; the author says Windows is untested.
- Under the GPL-2.0 license, changes to the code of a hosted copy must be published under the same license.
Key features
sitespeed.io
- HTML test reports
- Each run reports Core Web Vitals against Google's thresholds, with a filmstrip and video of the load, a HAR waterfall, CPU timeline and the Coach's advice.
- Real browsers and phones
- Tests in Firefox, Chrome and Edge, on Chrome for Android and Safari on iOS over USB, with network throttling to emulate real connections.
- Scripted user journeys
- Scripts can test several URLs, log in, or add items to a cart, and single-page applications are supported.
- Dashboards and monitoring
- A Docker Compose setup runs sitespeed.io with Graphite and Grafana and ready-made dashboards, for scheduled tests tracked over time.
- Budgets and CI
- Performance budgets can fail a build, with JUnit or TAP output for Jenkins, CircleCI, GitLab CI and GitHub Actions, and alerts on regressions.
- Plugins and other tools
- Plugins run Lighthouse, PageSpeed Insights, CrUX data collection, axe accessibility checks and statistical comparison of runs.
Yellow Lab Tools
- Scored page audit
- Gives a global score out of 100 and a grade per rule, grouped as network, images, DOM, JavaScript, jQuery, CSS, web fonts and server config.
- Offenders and score gain
- Each rule lists the files, selectors or functions at fault and says how many points the global score would gain if it were fixed.
- Device and access settings
- Simulates a phone, tablet or desktop, and can send cookies, basic HTTP login details or a proxy, or block and allow chosen domains.
- Public API
- A REST API on yellowlab.tools queues runs, reports their status and returns the full JSON result or parts of it, with CORS allowed.
- Command line and Node module
- Installed from npm, the yellowlabtools command tests a page and prints the result as JSON or XML, with an optional screenshot.
- Private server
- The server code can be installed on your own machine or run from a community Docker image, for testing pages on localhost or an intranet.
Plans
sitespeed.io
Open source$0
The full toolkit, self-hosted. The project puts a single cloud server plus S3 storage at around $500 a year.
Yellow Lab Tools
Free$0
The public instance at yellowlab.tools, its REST API, the npm command-line tool and the open-source server.
Common questions
Which is cheaper, sitespeed.io or Yellow Lab Tools?
As of Oct 23, 2026, both sitespeed.io and Yellow Lab Tools are free to use.
Which has a free plan, sitespeed.io or Yellow Lab Tools?
As of Oct 23, 2026, both sitespeed.io and Yellow Lab Tools have a free plan.
Which platforms do sitespeed.io and Yellow Lab Tools run on?
As of Oct 23, 2026, only sitespeed.io lists a Windows app and only Yellow Lab Tools lists a web app. Both list macOS and Linux apps. A platform missing from a listing is one its maker's pages did not mention.
More comparisons
How this page was made
- The verdict at the top follows a fixed rule. When both tools are in the same category and either is in our top three for it, the verdict follows that ranking: the higher-placed tool is our pick. The top three weigh who each tool suits as well as its grades, so a pick can go against the GPA. Otherwise the page does not pick one and says which grades higher: the higher GPA first; on a tie, the one with a free plan, then the one that starts cheaper in dollars a month, counted the same way for both; if they are still level, what the choice depends on.
- The grades are our own, from each tool’s review or report card. The GPA is their average.
- Prices, plans and platforms come from each tool’s listing. The table above says where each price was read and when.
- The differences and the answers to the questions are worked out from those listings.