Developer tools
Format JSON, encode and decode Base64 and URLs, generate UUIDs and hashes, test regular expressions and read JWTs. Everything runs locally, so tokens and payloads stay on your machine.
Tools in this category
8 tools-
Base64 encoder and decoder
Convert text or a local file to Base64 and back, without uploads. -
Hash generator
MD5 and SHA checksums of text or files, with an HMAC key and a compare field. -
JSON formatter
Format, minify and check JSON, with the line and column of the first error. -
JWT Decoder
Read token contents and dates. Signatures are not verified. -
Regex tester
Test a pattern, inspect its groups and preview your replacement. -
Unix timestamp converter
Convert Unix seconds or milliseconds to UTC dates, and back. -
URL encoder and decoder
Encode text for URLs or decode percent escapes as you type. -
UUID generator
Create secure random v4 or timestamp-based v7 UUIDs in batches.
Use these tools to inspect a JSON response, decode Base64, check a JavaScript regular expression or read JWT fields. JSON formatting and token decoding do not prove that the data is trustworthy; the JWT decoder does not verify signatures. Base64 processes text up to 1 MiB and files up to 10 MiB in a worker after you start the action. The hash generator uses incremental implementations and reads files in chunks, with up to 20 files per run. Check each tool’s limits before processing a large input. Some tools store settings or put input in the page URL; read their notices before sharing a link. Local processing does not protect secrets from browser extensions or a shared device. Prefer sanitized examples instead of live credentials.
Common questions
Can I safely paste API keys and tokens into these tools?
The tools process input locally, but that is not a guarantee that credentials are safe. Browser extensions, shared devices and copied page URLs can expose information. Use sanitized examples where possible, check the tool’s storage and URL notices, and never share a link containing a secret.
Do the hash tools support files?
Yes. The hash generator accepts files of any size and reads them in chunks inside a Web Worker, so the page stays responsive. The file is never uploaded. MD5 is provided for legacy checksums; use SHA-256 or stronger for anything security related.