Discover the Best Free Online Tools for Every Task
Devnitys is a curated directory of the best free online tools for images, PDFs, text, developers, SEO, and productivity. Find the right tool for any task in seconds.
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.
