Focus Developers

Posted on Mar 29

I Built 55+ Free Developer Tools in One Place, Here's Why

#webdev #ai #javascript

The Problem

Every day I'd bounce between 5-10 different sites just to do basic tasks like format some JSON here, decode a JWT there, count tokens somewhere else. Each site had its own ads, popups, and login walls.

So I built UtilHub - one place for everything.

🔗 utilhub.in

What's Inside

55+ tools across 6 categories:

AI & LLM Tools (the differentiator)

Token Counter - count tokens for Claude, GPT-4o, Gemini, Llama side by side
LLM Pricing Comparison - costs across all major providers
Prompt Injection Tester - test system prompts against common attacks
Context Window Visualizer - see how much context you're actually using
AI Model Comparison - benchmarks, speed, cost at a glance
API Request Builder - generate Claude/OpenAI API calls visually

Classic Dev Tools

JSON Formatter & Validator
Regex Tester with explanations
JWT Decoder
Base64 Encode/Decode
Hash Generator (MD5, SHA1, SHA256, SHA512)
Diff Checker
Cron Expression Builder
UUID Generator
...and 40+ more

What Makes It Different

1. AI tools nobody else has
Sites like 10015.io and it-tools.tech are great, but they have zero AI/LLM tools. That's the gap I'm filling.

2. Everything runs client-side
Nothing leaves your browser. No data is sent to any server. Paste your API keys, JWT tokens, or private JSON - it stays on your machine.

3. Zero friction
No signup. No login. No usage limits. No popups. Open the tool, use it, done.

4. Fast
Static HTML on Cloudflare's CDN. Every tool loads instantly because it's pre-rendered at build time.

Tech Stack

Next.js 16 (App Router, static export)
Tailwind CSS 4 + shadcn/ui
Cloudflare Pages (unlimited bandwidth, free tier)
Playwright for e2e testing (121 tests)

The entire site generates as static HTML/CSS/JS no server, no cold starts, no database.

Total hosting cost: $0/month.

What's Next

More AI tools (embedding visualizer, RAG chunking calculator)
Shareable URLs (encode tool state in the URL)
PWA offline support for all client-side tools

Try It