Fast viewer for large JSON files (up to 50 MB in the browser) with a collapsible tree view, text/RegEx search, copy-path
Developer Tools
Fast viewer for large JSON files (up to 50 MB in the browser) with a collapsible tree view, text/RegEx search, copy-path, and export of the whole file or a selected branch to JSON (formatted or minified) or CSV. Opens local files, pasted data, or URLs, including Basic/Bearer-authenticated API endpoints. Runs client-side, so no data leaves your machine.
Dynamic, interactive ER-style exploration for large and complex databases: search, follow relations, find paths, and bui
Developer Tools
Dynamic, interactive ER-style exploration for large and complex databases: search, follow relations, find paths, and build focused layouts incrementally; the explorer works with no account, though saving layouts and documentation may require one.
Make a looping 9:16 Canvas video, artist header, avatar and cover art for a Spotify release. Encodes in the browser with
Image Tools
Make a looping 9:16 Canvas video, artist header, avatar and cover art for a Spotify release. Encodes in the browser with WebCodecs, so files are never uploaded.
Free in-browser audio test toolkit with stereo left/right channel test, frequency sweep, tone generator, bass response t
Generators
Free in-browser audio test toolkit with stereo left/right channel test, frequency sweep, tone generator, bass response test, headphone test and tinnitus frequency test. All tests run client-side, bilingual EN/ZH.
Free browser-based Lottie animation tool. Preview .json and .lottie files, edit colors across all layers, and convert be
Image Tools
Free browser-based Lottie animation tool. Preview .json and .lottie files, edit colors across all layers, and convert between formats. No account required.
Draw and edit paths, areas and markers on a map. Supports GeoJSON, GPX, KML and KMZ files, with routing, elevation profi
Design Tools
Draw and edit paths, areas and markers on a map. Supports GeoJSON, GPX, KML and KMZ files, with routing, elevation profiles and shareable links. Files are processed in your browser. Open source.
Finds the dates a group can travel together: everyone taps the days they are free and it ranks the consecutive date rang
Productivity
Finds the dates a group can travel together: everyone taps the days they are free and it ranks the consecutive date ranges that fit the most people. Days only, so no time-of-day scheduling.
Checks robots.txt, page-level crawler directives, and responses to documented ChatGPT and Claude crawler user-agent name
Developer Tools
Checks robots.txt, page-level crawler directives, and responses to documented ChatGPT and Claude crawler user-agent names without login; it cannot verify official provider IPs.
