10 Free Developer Tools That Don't Require Signup (2026)
DevToolKitTired of "free" tools that need your email, credit card, and a blood oath? Here are 10 developer tools that actually work with zero signup.
1. Password Strength Checker
How long would a hacker take to crack your password? Get entropy analysis, attack scenarios (from online brute force to nation-state GPU clusters), and specific improvement tips.
100% client-side — your password never leaves your browser.
2. Website Down Checker
Is that site down for everyone or just you? Check any domain instantly. Shows HTTP status, response time, IP address, and SSL certificate status.
3. Website Security Scanner
Scans any domain for SSL/TLS issues, missing security headers, DNS misconfigurations, and more. Returns a security grade.
4. JSON Diff Tool
Paste two JSON objects and see differences highlighted. Perfect for comparing API responses or config files.
5. Regex Tester
Write and test regular expressions with real-time matching, capture groups, and match details.
6. Cron Expression Explainer
Paste a cron expression, get plain English explanation and the next 5 scheduled run times. Never guess cron syntax again.
7. JWT Debugger
Decode any JSON Web Token instantly. See header, payload, and expiration. 100% client-side.
8. Sats Calculator
Convert between BTC, satoshis, and USD with live exchange rates.
9. Free API Directory
Curated list of free public APIs that work without API keys. Includes curl examples for each.
10. REST API Hub (30 endpoints)
SSL checks, DNS lookups, email validation, hashing, UUID generation, QR codes, crypto prices, base64, JWT decode, cron parsing, and website status checks. All free JSON endpoints.
Why These Exist
I was spending $150+/month on SaaS dev tools that are essentially thin wrappers around basic functionality. So I built free alternatives on a $5 VPS.
All tools are free, with no tracking, no analytics, and no ads. If you find them useful, you can tip via Lightning: devtoolkit@coinos.io