• 10 Free Developer Tools That Don’t Need an Account
  • 1. Password Strength Checker
  • 2. Website Down Checker
  • 3. Website Security Scanner
  • 4. JSON Diff Tool
  • 5. Regex Tester
  • 6. Cron Expression Explainer
  • 7. JWT Debugger
  • 8. Sats Calculator
  • 9. Free API Directory
  • 10. REST API (30 endpoints)
  • Why I Built This

§10 Free Developer Tools That Don’t Need an Account

I’m tired of “free” tools that require signup, email verification, and your firstborn child. So I built alternatives. All free. No accounts. No tracking.

§1. Password Strength Checker

How long would it take to crack your password? Get entropy analysis, attack scenarios (GPU cluster to nation-state), and improvement tips. 100% client-side — your password never touches a server.

→ Try it

§2. Website Down Checker

Is that site down for everyone or just you? Check HTTP status, response time, SSL cert status, and server headers.

→ Try it

§3. Website Security Scanner

Checks SSL/TLS, security headers, DNS config, open ports, and more. Get a security grade for any domain.

→ Try it

§4. JSON Diff Tool

Paste two JSON objects, see the differences highlighted. Great for comparing API responses or config changes.

→ Try it

§5. Regex Tester

Write and test regular expressions with real-time matching. Shows capture groups and match details.

→ Try it

§6. Cron Expression Explainer

Paste a cron expression, get plain English and the next 5 scheduled run times.

→ Try it

§7. JWT Debugger

Decode JSON Web Tokens instantly. See header, payload, and expiration. Everything stays in your browser.

→ Try it

§8. Sats Calculator

Convert between Bitcoin, satoshis, and USD in real-time. Uses live exchange rates.

→ Try it

§9. Free API Directory

Curated list of free public APIs that don’t need an API key. Categories include weather, crypto, news, and dev tools.

→ Browse APIs

§10. REST API (30 endpoints)

SSL checks, DNS lookups, email validation, password hashing, UUID generation, QR codes, crypto prices, base64, JWT decode, cron parsing, and site status checks. All free, all JSON.

→ API Docs

§Why I Built This

I was spending $150+/month on various SaaS dev tools. Most of them are simple wrappers around basic functionality that any VPS can handle.

So I put it all on a $5 Hetzner VPS. Total cost: $5/month for everything.

If you find these useful, consider zapping some sats: ⚡ devtoolkit@coinos.io

The whole thing runs on Node.js, nginx, and PM2. No databases. No Docker. No Kubernetes. Just simple code that works.