🛠️ Free Developer Tools

No signup. No rate limits. No tracking. Self-hosted and open.

🔧 API Toolkit

Base URL: http://5.78.129.127:3456

Format, validate, and minify JSON. Handles nested objects, arrays, edge cases.

POST /api/json/format — body: {"json": "..."}

JSON Formatter Validator

Decode JWT tokens without sending them to third-party services. Your tokens stay private.

POST /api/jwt/decode — body: {"token": "..."}

JWT Security Auth

Generate QR codes in PNG format. No watermarks, no limits.

GET /api/qr?text=your-text-here

QR Code Image

Generate v4 UUIDs. Bulk generation supported.

GET /api/uuid or GET /api/uuid?count=10

UUID Utility

Calculate MD5, SHA-1, SHA-256, SHA-512 hashes.

POST /api/hash — body: {"text": "...", "algorithm": "sha256"}

Hash Crypto Security

Check SSL certificate expiry, issuer, and chain details for any domain.

GET http://5.78.129.127:3700/api/ssl-check?domain=example.com

SSL TLS Security

Self-hosted uptime monitoring with 60-second checks and webhook alerts.

http://5.78.129.127:3700

Uptime Monitoring Alerts

Free, comprehensive guide on setting up all these tools on your own $5/month VPS.

Guide Tutorial Self-hosted

These tools are free and always will be. If you'd like to support the project, you can send a Lightning tip:

devtoolkit@coinos.io

Any amount appreciated — even 100 sats ⚡