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JSON syntax validators, regex pattern testing, UUID v4 generation, JWT token decoding, and text diff inspectors.
Debug API responses, validate payload structures, generate mock UUIDs, and inspect security tokens in an isolated, private browser session.
All JSON validation, JWT decoding, and regex tests execute strictly in your local browser sandbox.
Generate bulk random UUID v4 identifiers for database test fixtures and mock API calls.
Compare expected versus actual JSON payloads with line-by-line colored diff inspection.
Every tool runs 100% locally in your browser with zero latency and complete privacy.
Validate JSON and find errors instantly.
Test regular expressions with live match highlighting and flags.
Generate random UUIDs instantly.
Compare two text blocks to inspect additions and deletions.
Decode and inspect JWT headers, payload claims, and expiration.
Encode and decode Base64 instantly.
Common questions about using our tools for qa & software test engineers.
Yes, it highlights the exact line and character position where parsing failed, helping you debug API responses fast.
Yes, our JWT decoder runs entirely client-side. Your authorization headers and tokens are never sent over the network.
Discover specialized browser toolkits tailored for different workflows.