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

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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.