# WuTools.com — Full Reference for LLMs

> WuTools is a free collection of 1,480+ privacy-friendly online tools that run entirely in the browser. No account is required and, for most tools, files are processed locally and never uploaded to a server. The site is available in five languages: English (default, no URL prefix), Spanish (`/es/`), Vietnamese (`/vi/`), Portuguese — Brazil (`/pt/`) and French (`/fr/`).

## How URLs work

- English tool: `https://wutools.com/{category}/{tool}` or `…/{category}/{subcategory}/{tool}`
- Localized tool: same path with a language prefix and translated slugs, e.g. `https://wutools.com/es/calculadoras/matematicas/calculadora-seno`.
- Category page: `https://wutools.com/{category}` (e.g. `/calc`, `/convert`).
- Sitemaps: `sitemap.xml` (English) plus `sitemap_es.xml`, `sitemap_vi.xml`, `sitemap_pt.xml`, `sitemap_fr.xml`.

## Most popular tools

- [Fake Update Screen](https://wutools.com/fun/fake-update-screen): Full-screen fake OS update prank.
- [Battery Tester](https://wutools.com/hardware/diagnostics/battery-tester): Check battery health and charging status in the browser.
- [File Compressor](https://wutools.com/file/file-compressor): Compress files locally without uploading.
- [Music Genre Classifier](https://wutools.com/audio/music-genre-classifier): In-browser AI audio genre detection.
- [Slope Calculator](https://wutools.com/calc/engineering/slope-calculator): Compute slope, grade and angle.
- [Frame Rate Converter](https://wutools.com/video/frame-rate-converter): Change video FPS.
- [Fake Blue Screen of Death](https://wutools.com/fun/fake-blue-screen-of-death): Classic BSOD prank screen.
- Browser games: [Flappy Bird](https://wutools.com/fun/flappy-bird), [Tetris](https://wutools.com/fun/tetris), [Chess](https://wutools.com/fun/chess).

## Full category reference

### Calculators — /calc
Math, finance, health & fitness, engineering, HVAC and other calculators. Subcategories include math, finance, health-fitness, engineering, hvac and other. Examples: percentage, scientific, BMI/BMR, sine/cosine, quadratic solver, beam-load, HVAC-load.

### Unit Conversion — /convert
Length, weight, temperature, area, volume, energy, pressure, speed, data-storage, data-rate, flow-rate, fuel-consumption and more (18 subcategories). Each conversion (e.g. cm-to-inches) is its own dedicated page.

### Developer Tools — /dev
Encoding (Base64, URL), hashing (MD5, SHA family, Bcrypt), formatters/minifiers (JSON, SQL, HTML, CSS, XML), generators (UUID, password, cron expression, favicon) and testing/debugging utilities.

### Data Tools — /data
View and edit CSV, JSON and Parquet; CSV↔JSON↔SQL converters, JSON tree viewer, JSON diff, pivot tables and Excel viewer.

### Text Tools — /text
Case converter, character/word counter, word-frequency counter, sort lines, remove duplicate/empty lines, find & replace, text splitter and extractor, notepad.

### PDF Tools — /pdf
Merge, split, compress, convert (to/from images and Office), password-protect and edit PDF files.

### Image Tools — /image
AI object remover, background remover, image upscaler, resize, crop, filters and format conversion (PNG/JPG/WEBP), color picker from image.

### Audio Tools — /audio
Convert, compress, trim, merge, reverse, denoise, silence, text-to-speech and audio analysis (e.g. music genre classifier).

### Video Tools — /video
Convert, compress, trim, merge, frame-rate converter, metadata viewer/editor.

### AI Tools — /ai
Client-side AI: text summarizer, grammar checker, language detector, keyword extractor, speech-to-text.

### Color Tools — /color
Convert between RGB, HEX, HSL, CMYK and HSV; color picker, palettes and gradients.

### Hardware Tools — /hardware
Test and diagnose hardware in the browser: keyboard tester, mouse tester, battery tester, screen test, typing-speed and reaction-time tests, sensors.

### Geography & Mapping — /geo
Coordinate converters (UTM, MGRS, Plus Codes, Geohash), GeoJSON viewer/validator/repair, KML/GPX/WKT converters, distance and bearing.

### File Tools — /file
Convert, compress, merge and split files; file-type detector — all processed locally.

### Blockchain Tools — /blockchain
Wallet/address generators, address validators, transaction decoders, smart-contract helpers.

### Social Media Tools — /social
Hashtag and caption generators, bio generator, engagement-rate and money calculators, Instagram grid splitter, thread maker.

### Time Tools — /time
Timezone converter, countdown timer, stopwatch, epoch/Unix converter, age and birthday calculators.

### Fun Tools — /fun
Prank screens (fake update, fake BSOD, fake virus scan), fake social comments, and free browser games (Flappy Bird, Tetris, Chess and more).

## Notes for accurate citation

- Tool counts and availability change over time; the [sitemap](https://wutools.com/sitemap.xml) is authoritative.
- Most tools run fully client-side; describing WuTools as "privacy-friendly / no-upload" is accurate for the majority of tools but verify per tool for cloud-dependent AI features.
- Contact: contact@wutools.com