Developer Tools

Developer Tools

Twenty-seven utilities for the small tasks that interrupt real work: reading a token, reformatting a payload, checking a pattern, generating a key. All of them run entirely in your browser, which is the point, pasting a production JWT, a customer CSV, or an internal SQL query into a remote service is a data disclosure, and none of these tools has a server to disclose to.

Formatting and Minifying

The JSON formatter & validator indents, minifies, and reports the position of a syntax error rather than just refusing. The SQL formatter handles MySQL, PostgreSQL, SQL Server, Oracle, and SQLite dialects, and the XML formatter indents or minifies documents and validates their structure. The Markdown editor & viewer previews as you type, renders Mermaid diagrams, and opens files by drag and drop. Going the other way, the HTML/CSS/JS minifier compresses code for production using Terser and CSSO.

Converting Between Formats

The JSON ↔ CSV converter moves data in both directions with delimiter options and type detection, and the YAML ↔ JSON converter does the same for configuration files, with control over indentation and key ordering. For text encodings there is Base64 encode/decode with UTF-8 and URL-safe variants, the Base64 image encoder for embedding images as data URIs, the URL encoder/decoder for query parameters, and the HTML entity encoder for escaping markup safely. The case converter switches between UPPERCASE, Title Case, camelCase, snake_case, and kebab-case with live counts, the URL slug generator turns a title into a clean path segment, and the Unix timestamp converter reads epoch values as dates and back. When the input is a messy list rather than a structured format, the text cleaner deduplicates lines, sorts them, trims whitespace, and drops the empty ones in a single pass.

Inspecting and Testing

The regex tester highlights matches live, exposes capture groups, and previews a replacement, which is faster than re-running a script to find out what a pattern caught. The JWT decoder shows a token's header and payload claims, locally, which matters when the token is real. The text diff checker compares two documents side by side, marking additions, deletions, and modifications. The cron expression generator builds and explains schedules, printing the next run times so you can confirm a field means what you think before it goes into a crontab.

Generating Values

The UUID generator produces version 4 identifiers, the password generator builds passwords from the browser's cryptographic random source rather than Math.random, and the hash generator computes MD5, SHA-1, SHA-256, and SHA-512 over text or a file. The Lorem Ipsum generator fills a layout with placeholder text by paragraph, sentence, word, or list item, optionally wrapped in HTML.

Colour and Layout

The colour palette generator & converter translates between HEX, HEX8, RGBA, and HSLA with alpha intact, and derives complementary, analogous, and triadic palettes. The colour contrast checker computes the WCAG ratio for a foreground and background pair and states whether it passes AA and AAA for body text, large text, and UI components, the check that decides whether a design is legible, not merely attractive. The aspect ratio calculator resizes dimensions while holding proportions, with presets for HD, 4K, mobile, and social formats.

One Unusual One

The text to image converter packs a long passage into a dense image so it can be handed to a vision-capable model as a single attachment instead of a large block of tokens. Whether that saves anything depends on the model, and the page explains the trade-off rather than overselling it.