Our story
Small developer chores shouldn't mean pasting your data into a stranger's website.
I'm Johnny Mobley. I started building systems for other people in 2000, when I was 16, and I've been doing it ever since. Along the way I automated most of my own work, and the tools I built for myself became these companies. Each one runs on rules I wrote down, not on paid AI calls, which is why it can cost so little.
Formatting a blob of JSON, decoding a token, turning a Unix timestamp into a date: these come up several times a day, and the usual answer is to search for a site that does it and paste the text in. I didn't like sending tokens and payloads to pages I knew nothing about.
So devtoolbx runs those conversions in your own browser tab. The code is on the page, nothing you type in the toolbox is sent to a server, and there's no account. It is a handful of tools, not a full suite.
What works today
- Formats and validates JSON
- Encodes and decodes Base64 and URL-encoded text
- Makes a SHA-256 hash of any text and generates random v4 UUIDs
- Converts Unix timestamps to dates and back
- Decodes a JWT's header and payload (it does not check the signature)
What it doesn't do yet
DevUtils still does things devtoolbx doesn't:
- A desktop app that works offline and picks the right tool from your clipboard.
- Beautifiers and minifiers for HTML, CSS, JavaScript, XML and SQL.
- Converters between JSON, YAML and CSV, and code generators like cURL to code.
- A text diff checker, Markdown preview, cron parser, QR codes and dozens of other tools.
What it costs
| What you get | Price | |
|---|---|---|
| DevUtils Basic license, one Mac, one-time purchase | A native macOS app with 47+ offline tools (JSON, Base64, JWT debugger, regex tester, text diff, converters and more) and one year of updates. | $29 once |
| devtoolbx | Everything above, in the browser, no account. An optional $4 30-day pass only raises the result count on the site's GitHub repository search. | Free |
DevUtils's price is from their pricing page as of October 29, 2026. Prices change, so check theirs before you compare.
Open devtoolbx— Johnny