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Developer Tools

15 tools

Formatters, validators, encoders, hashes, and converters for everyday dev work.

About Developer Tools

Developer Tools bundles fifteen utilities that we reach for in everyday engineering work: JSON, HTML, CSS, SQL, and XML formatters; bidirectional converters between JSON and XML; Markdown to HTML and HTML to Markdown; Base64 and URL encoding; JWT inspection; and SHA-256 and MD5 hashing. Each runs locally in your browser using the Web platform and lightweight, audited libraries. Nothing is uploaded — your code, tokens, and payloads stay on your machine.

If you are debugging an API response, sanity-checking a JWT, or pretty-printing a query before pasting it into a ticket, you should find the right tool in two clicks. The formatters use real parsers (not regex) so they preserve semantics, and the syntax-highlighted CodeMirror editor on every formatter page works well with payloads up to several megabytes.

Frequently asked questions

Do these developer tools work on confidential data?+

Yes. Every developer tool runs in your browser using JavaScript — no payload, token, or hash input is transmitted to a server. This is a hard architectural property of the site, not a configuration toggle.

Which SQL dialects does the SQL Formatter support?+

Standard SQL, PostgreSQL, MySQL, SQLite, T-SQL (MSSQL), and BigQuery. Pick a dialect from the dropdown for accurate keyword handling.

Does the JWT Decoder verify the signature?+

No — it only decodes the header and payload so you can inspect claims. Signature verification requires the issuing secret or public key and must be done on the server.

Why use SHA-256 instead of MD5?+

SHA-256 is collision-resistant and is what you want for any security-sensitive use. MD5 is fast and still appropriate for non-security checksums (file integrity within a trusted system).