Why I built this

Look, here's the thing. I run a small web agency in the Czech Republic. We build e-shops, company websites, custom apps - the usual stuff. And every single day, I'm formatting JSON from some API, testing regex patterns, decoding JWTs when auth breaks, encoding stuff to Base64. You know the drill.

The online tools out there? Most of them are garbage. Either they take forever to load, or they're covered in those sketchy ads, or - and this really got to me - they send your data god knows where. Last year I almost pasted a client's production JWT into some random online decoder. Caught myself just in time. That was my "okay, I'm building my own tools" moment.

So yeah, CodeUtil exists because I needed it. Everything runs in your browser. Your data stays on your machine. I don't even have a backend that could store anything if I wanted to. And it's free because honestly, charging for something this simple feels wrong.

What makes it different

Privacy First

Everything runs client-side. Your API keys, tokens, and code never touch any server.

Fast

No backend calls, no waiting. Just instant results in your browser.

Free, Really

No premium tiers, no usage limits, no "sign up for more features" popups.

Works Offline

Once loaded, the tools work without internet. Use them anywhere.

Who am I

MŠ

I'm Martin Šikula. I run Šikulovi s.r.o. - a tiny web agency based in the Czech Republic. Been doing this for about 15 years now. Still haven't figured out why clients always want changes on Friday afternoon.

CodeUtil isn't some grand vision. It's literally just the tools I got tired of googling for every week. If they're useful to you too, great. If not, no hard feelings.

More about me

About CodeUtil