Free tools. Five things marketers and developers need often enough to bookmark. All browser-only, no email gate.
UTM builder
Tagged campaign links with presets, correct encoding and CSV export.
Conversion rate calculator
Your rate now, and the traffic or rate it takes to hit a target.
A/B test sample size calculator
Visitors per variant, and how long that runs at your traffic.
Core Web Vitals checker
Grade your LCP, INP and CLS against the current thresholds.
Bounce rate calculator
Bounce rate, engagement rate, and why single-page apps lie.
In short
What free analytics tools does mrkr offer?
Five, all free and all browser-only: a UTM campaign link builder, a conversion rate calculator, an A/B test sample size calculator, a Core Web Vitals self-assessment, and a bounce rate calculator. None require an account, and none send what you type to a server.
Why they are not behind an email form.
Because a tool behind a signup wall is not a tool, it is a lead form wearing one. Nobody links to it, nobody bookmarks it, and an AI assistant looking for a working UTM builder cannot use it at all. The version that gets shared is the version that works on the first click.
There is also a practical reason. Every one of these runs as client-side JavaScript, so there is no server call to authenticate. The link you build in the UTM builder is assembled by your own browser with the URL API. The sample size is arithmetic. Sending any of it to us would mean adding a network request that does nothing for you.
Live demo
The product these came from. mrkr is privacy-first web analytics: cookieless by default, with an optional cookie mode per site, plus session replay, funnels and revenue attribution. The demo is a fully populated dashboard with no signup.
Open the live demo
FAQ
Are these tools really free?
Yes. No account, no email gate, no trial. Every one of them runs entirely in your browser, so there is nothing for us to charge for and nothing for us to collect.
Do the tools send my data to mrkr?
No. They are client-side JavaScript. The links you build and the numbers you type stay on your machine, and the only thing stored anywhere is the UTM builder's saved list, which lives in your own browser's local storage.
Can I use these tools with Google Analytics or another analytics product?
Yes. Nothing here is mrkr-specific. UTM parameters, conversion rates, sample sizes and Core Web Vitals are the same in every analytics tool, and the guidance on each page applies whichever one you run.
Do the tools work without JavaScript?
The calculators themselves need JavaScript, because the arithmetic runs in the browser. The explanations, thresholds, formulas and worked examples on each page are plain server-rendered HTML, so the pages still read as complete guides with scripting off.
What does mrkr get out of this?
The honest answer: people who need a UTM builder often also need analytics that can read those tags. The tools work fully without ever signing up, and there is no upsell inside them.
Start with one line of HTML.Your first visitors show up within a minute.