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MP Software studio
MP Software studio

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I Built a UUID Generator and Cron Expression Builder — Both Run 100% in Your Browser

I just shipped two more developer tools on EveryTool — and both are ones I personally kept Googling repeatedly before finally just building them properly.

🔑 UUID Generator

Need a UUID? Most devs just search "UUID generator online," click the first result, and hope it's not doing something sketchy with the output.

The EveryTool UUID Generator:

  • Generates v1 (time-based) and v4 (random) UUIDs
  • Supports bulk generation — need 50 at once? Done.
  • Copy to clipboard in one click
  • Runs entirely client-side using the native crypto.randomUUID() API — nothing leaves your browser

No tracking. No ads. No "sign up to generate more."


⏰ Cron Expression Builder

Cron syntax is one of those things that never fully sticks. Is it 0 9 * * 1 or * 9 0 * 1? I always end up on crontab.guru double-checking.

The EveryTool Cron Expression Builder offers:

  • A visual field-by-field builder (minute, hour, day, month, weekday)
  • Human-readable preview — see exactly what your expression means in plain English
  • Real-time validation so you catch errors before they hit production
  • Common presets (every hour, every day at midnight, every Monday, etc.)

Again — fully client-side, no backend involved.


Why client-side only?

EveryTool is built on a single principle: your data doesn't leave your browser.

No file uploads to a server. No accounts. No usage tracking. Just tools that work, fast, in your browser tab.

The stack is Next.js App Router + TypeScript + TailwindCSS, deployed on Vercel. For cryptographic operations like UUID generation, I use the Web Crypto API directly rather than pulling in an external library.


Where things stand

We're now at 33+ tools across four categories:

  • 🖼️ Image Tools
  • 📄 PDF Tools
  • 🧮 Calculator Tools
  • 🛠️ Developer Tools

Developer Tools is the most active area right now. Recent additions include Base64 Encoder/Decoder, URL Encoder/Decoder, Hash Generator, JWT Decoder, Regex Tester, and Color Code Converter.


What's next?

I'm continuing to expand the Developer Tools category. If there's a tool you constantly Google or find yourself copy-pasting from Stack Overflow, let me know in the comments — it might be next on the list.

👉 Try the tools at everytool.solutions


Building this in public — follow along on Twitter/X and LinkedIn for updates.

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