Browse by tag

Developer utilities. Format conversion, prettifying, encoding / decoding, regex testing and similar dev workflow helpers.

Tools that translate one format into another, across images, audio, video, text, and numeric representations.

Calculators for tax, pension, investments, unit conversion, and other numeric workflows.

Tools that operate on images: resize, crop, format conversion, EXIF strip, background removal, all in-browser.

General-purpose text utilities: formatting, find-and-replace, counting characters / words / lines, diff, sorting.

Tools that pull specific elements (text, audio, frames, embedded images) out of PDFs, videos, images, and archives.

Tools that work with audio files — record, convert, cut, merge, denoise, transcribe — all in the browser.

Money-related calculators. Japanese income tax, residence tax, pension, investment simulation, currency conversion.

Time, date, and timer utilities. Timezone conversion, date arithmetic, Pomodoro, interval timer and more.

Generators for QR codes, barcodes, passwords, UUIDs, lorem ipsum, and similar synthetic data.

Tools that work with video files: convert, cut, compress, GIF export, audio extraction — all powered by ffmpeg.wasm locally.

Tools that operate on PDF files: merge, split, compress, unlock, extract images, without sending the PDF anywhere.

Tools for Japanese text: furigana, half-width / full-width conversion, mojibake recovery, kanji readings.

Japan-specific tax tools — income tax, residence tax, consumption tax, hometown tax (furusato nōzei).

Color utilities: HEX / RGB / HSL / OKLCH conversion, contrast checking, gradient builders.

Tools that decode encoded strings and tokens to inspect their contents — Base64, JWT, URL, Quoted-Printable, and so on.

Tools that pretty-print and reformat text such as JSON, YAML, SQL, CSS, and Markdown.

Security and privacy-related utilities — password strength, hashing, JWT verification, EXIF stripping.

Tools that encode text or files into another representation — Base64, URL, Punycode, Quoted-Printable, and so on.

Tools that format, validate, transform, and query JSON.

Tools that combine multiple files into one — PDF merge, video merge, audio merge, text concatenation, and similar.

Tools that convert Markdown to HTML, plain text, or table-of-contents.

Tools that encode / decode / parse URLs and manipulate query parameters.

Tools that overlay watermarks on images and videos.

Tools that inspect and remove EXIF metadata (capture timestamp, GPS, camera model) from images.

Tools that visualise differences between texts and files.

Tools that work with tempo — BPM detection, metronome.

Tools that break a single file into pieces — PDF, video, audio, CSV, and string splitters.

Tools that count characters, words, lines, tokens, and other text metrics.

Tools that trim unwanted regions from images and videos.

Tools that run AI models locally in the browser via Transformers.js / ONNX. Background removal and transcription belong here.

Tools that compute MD5, SHA-1, SHA-256, CRC, and other digest values.

Tools that test, replace, and explain regular expressions.

Tools that reduce file size for PDFs, images, videos, and audio.

Tools that change image and video resolution.

Tools that rotate images and videos in 90° / 180° steps.

Tools to decode, verify, and create JSON Web Tokens.

Tools that play video or audio in reverse.

Tools that transcribe speech from audio and video using Whisper running locally in the browser.

Tools that mirror images and videos horizontally or vertically.

Tools that capture data from the device — microphone, screen recording, and similar.

Tools that reorder pages or elements inside a file (PDF page reorder and similar).

Tools that remove password protection from files (e.g. PDFs) when you know the password.