I stopped pasting JSON into random websites — 9 free dev utilities that don't want your email

I have a confession: for years my debugging workflow included pasting API responses, tokens, and log snippets into whatever formatter or decoder site Google threw at me. No adblock regrets can undo the times I decoded a JWT on a site that had twelve popups.

I built a small set of free browser tools for exactly this reason, so I want to be upfront: yes, these are my tools. But the point of this post stands even if you never click the links — stop handing your data to sites you wouldn't trust with your coffee order.

What I wanted was simple: paste, get the answer, leave. No account. No email. No "upgrade to format the rest of your file." Here's the kit I keep open in a tab group:

1. JSON formatter/validator — paste it, it's formatted and validated. Also converts JSON to CSV when the analyst asks for a spreadsheet.
2. Regex tester — live highlighting while you build the pattern, so you stop guessing and start shipping.
3. Base64 encoder/decoder — no mystery, does the thing.
4. JWT decoder — see the payload and header instantly. This is the one that made me stop pasting tokens into random decoders.
5. Cron expression builder — human-readable schedule next to the expression so "0 3 * * 1" stops being a quiz question.
6. Epoch converter — timestamps both directions, plus the human dates.
7. Markdown to HTML — for when the CMS wants raw HTML and you think in markdown.
8. Text diff — two files, instant diff, no repo needed.
9. Subnet calculator — CIDR math without the whiteboard.

None of them ask for an account. There's no signup wall, no freemium tier, no "create a free account to continue." You paste, you get the answer, you leave. That was the whole design goal.

My rules for trusting a utility site now, in case you're evaluating others:

• It should work before asking who you are. If the first screen is a signup form, it's not a tool, it's a funnel.
• Everything should run in your browser for things like formatting and decoding. If a "JSON formatter" needs a server round-trip, ask yourself why.
• It should not have seventeen ad trackers firing before the tool even loads.

The links, since you'll ask: the full set is at https://cyberscryb.com/tools/ — JSON formatter is https://cyberscryb.com/tools/json-formatter/, regex tester https://cyberscryb.com/tools/regex-tester/.

What tools are in your tab group? I'm always collecting good ones — the ones I trust enough to not ask for anything.

Nate Ady — founder of CyberScryb. I build free AI tools and dev utilities, no signup, no paywall.