Free Online Developer Tools
24+ fast, private developer tools — JSON validator, hash generator, UUID, Base64, regex tester, and more. No signup required.
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Free online developer tools: JSON/YAML validator, Base64 encoder, MD5/SHA hash generator, UUID/ULID generator, email validator, URL parser, color converter, regex tester, timestamp converter, diff checker, markdown preview, QR code generator, cron expression builder, and JWT decoder. All tools run locally in your browser — your data never leaves your device.