A collection of free online tools for testing, development, and productivity.
Create customizable social media posters for observance days with text, date, and background customization. Try it online
Features: Customizable text/date, font controls, Unsplash integration, PNG download
Environmental awareness poster creator with custom backgrounds and text styling. Try it online
Features: Custom backgrounds, text styling, font/layout adjustment, PNG export
Test SSE endpoints with real-time message viewing and story mode. Try it online
Features: Real-time messaging, story mode, connection status, error handling
Execute and test Lua scripts with Redis using Monaco Editor. Try it online
Features: Syntax highlighting, argument support, execution results, error debugging
Format, minify and validate JSON with exact error locations. Try it online
Features: Live validation, line/column errors, 2/4 space or tab indent, minify, sort keys, copy and download
Encode and decode Base64, Base64URL and URL (percent) encoding. Try it online
Features: Unicode-safe Base64 and Base64URL, URL component and full address modes, forgiving decoding, file to data URL, swap and copy
Decode JSON Web Tokens and verify their signatures without the token leaving your browser. Try it online
Features: Colour-coded token parts, readable exp/iat/nbf dates, expiry status, HS256/384/512 secret and RS/PS/ES PEM public key verification
Test JavaScript regular expressions with live match highlighting. Try it online
Features: Live highlighting, numbered and named groups, replace preview, all JS flags, runaway pattern protection, quick reference
Read cron expressions in plain English and see the next run times. Try it online
Features: Plain-English summary, field-by-field breakdown, next 5/10/20 runs in local time or UTC, names, steps, ranges, @daily macros, shareable links
Generate UUIDs and MD5/SHA hashes of text or files. Try it online
Features: UUID v4 and v7 in bulk, uppercase/no-hyphen/brace formats, UUID inspector with creation time, MD5, SHA-1, SHA-256, SHA-384, SHA-512, HMAC, file hashing, hex or Base64
Convert Unix timestamps to dates and back, across time zones. Try it online
Features: Live epoch clock, auto-detects seconds/ms/µs/ns, ISO 8601, RFC 2822, relative time, ISO week, date to timestamp in any IANA zone with DST handling, custom time zone list
Lightweight online text editor that saves as you type. Try it online
Features: Word, character and line counts, Markdown-style bold/italic/underline shortcuts, copy, .txt download, auto-save
25/5 focus timer with a kanban task board. Try it online
Features: Pomodoro timer, To-Do / Doing / Done columns, saved in the browser
Calculate exam scores with negative marking support for competitive exams. Try it online
Features: Negative marking options (1/2, 1/3, 1/4, 2/3), instant score calculation, percentage display
Calculate how long you've lived and share with friends. Try it online
Features: Real-time countdown, shareable links, days/hours/minutes/seconds display
3x3 sliding puzzle game with custom image upload support. Try it online
Features: Custom image upload, move counter, completion celebration
Classic 9x9 Sudoku game with validation and completion effects. Try it online
Features: Interactive number input, validation, confetti on completion, mobile-friendly
Public chat room with no signup. Try it online
Features: Clickable links, name kept between visits
Share images in a public room. Try it online
Features: JPEG, PNG, GIF and WebP up to 15 MB
- Frontend: Astro, React, Vue, Svelte
- Styling: Tailwind CSS, Headless UI
- Graphics: react-konva, Canvas API
- Backend: Go (Redis/SSE servers), Next.js
- Deployment: Vercel