Top 5 Free Developer Tools for API & Data Security (2026)
Discover the best local-first developer tools for decoding JWTs, converting Base64 strings, testing Regex, and scrubbing secrets without sending any data to the cloud.
#1
Local-Only JWT Decoder
Analyze, debug, and inspect JSON Web Tokens safely.
Your tokens never leave your machine. All decoding happens securely inside your browser using client-side JavaScript. Paste your production tokens with 100% confidence.
Open JWT Decoder#3
Regex Tester & "Human Explainer"
Test regular expressions instantly. Our AST parser translates complex regex into plain English.
We use regexpp locally in your browser to deconstruct the regex AST tree and explain exactly what your pattern does step-by-step.
Open Regex Tester#4
Zero-Knowledge Secrets Scrubber
Detect and redact API keys, tokens, PII and secrets from logs, code, and config files.
Your text is scanned using regex patterns directly in your browser's memory. We cannot see, log, or transmit your secrets — even if we wanted to. Verify in DevTools → Network Tab.
Open Secrets Scrubber#5
JSON to TypeScript Converter
Instantly convert JSON responses into strictly typed TypeScript interfaces.
We don't send your API responses to any servers. The conversion happens securely and instantly in your browser via WASM/JS.
Open JSON to Code