How to Improve Developer Productivity: 9 Free Browser Tools That Do the Heavy Lifting

The most common time-sink in API development: copying a response from your terminal or Postman and trying to make sense of minified JSON. Paste it into the JSON Formatter and it's instantly readable — syntax highlighted, properly indented, with a tree view and an error detector that pinpoints the exact line of any issue. Supports format, minify, and validate modes.

Auth debugging is painful when you can't read the token. The JWT Decoder splits any token into its three parts, decodes the header and payload, and shows all claims in a readable format. exp, iat, sub, roles, custom claims — everything your application set when it signed the token. No secret key needed; the header and payload are only Base64url-encoded.

Writing a regex and guessing whether it matches is the definition of slow. The Regex Tester shows matches in real time as you type — highlighted in the test string, with a match list showing each captured group. Supports JavaScript regex flags (g, i, m, s). Save yourself the loop of write → run → adjust → repeat.

ORM-generated SQL and long ad-hoc queries are notoriously hard to read. The SQL Formatter takes any query — however long or messy — and formats it with consistent indentation, line breaks at clause boundaries, and keyword casing. Supports PostgreSQL, MySQL, SQLite, and T-SQL dialects. Paste in 500 lines of generated SQL and get readable output in a second.

Need test IDs for database fixtures, mock API responses, or seed data? The UUID Generator produces as many v4 UUIDs as you need in one click. Copy one or copy the entire batch. Faster than calling uuid() in a script when you just need a handful for a test case.

Basic auth headers, embedded images in HTML, and certain API payloads use Base64 encoding. The Base64 Encoder/Decoder handles both directions. Paste plain text to encode, or paste a Base64 string to see the decoded value. No copy-paste loop through the terminal.

Log files and database records that store timestamps as integers (1748044800, etc.) are impossible to read at a glance. The Unix Timestamp Converter goes both ways — paste an epoch timestamp to see the human date, or pick a date to get the timestamp. Works in seconds and milliseconds. Also shows the current timestamp so you have a reference point.

Paste two versions of a config file, SQL query, JSON blob, or any text and see exactly what changed — added lines in green, removed in red, unchanged greyed out. Useful for reviewing changes without a full git diff, comparing API response versions, or auditing config changes.

README files, technical documentation, PR descriptions, and Confluence pages all use Markdown. The live Markdown Editor shows a rendered preview in real time. Paste your Markdown to verify it renders correctly, or draft documentation without setting up a local preview environment.

All 9 tools in one place

JSON Formatter, JWT Decoder, Regex Tester, SQL Formatter, UUID Generator, Base64 Encoder/Decoder, Unix Timestamp Converter, Code Diff Checker, and Markdown Editor — all free, no signup, no limits.