All tools
Every tool on this page runs entirely in your browser — files are processed on your device and never uploaded. Only operations that are implemented and tested are shown.
Documents
Images
- JPEG compressor Reduce the file size of JPG photos and screenshots right in your browser. The image is decoded, re-encoded and saved on your device — no upload, no queue, no watermark. .jpg, .jpeg
- PNG compressor Make PNG files smaller in your browser with a genuinely lossless re-encode: identical pixels, identical transparency, smaller file. Optional lossy conversion to WebP is available when you want bigger savings and can accept a format change. .png
- WebP compressor WebP usually delivers the smallest images at good visual quality. Optimize existing WebP files or convert your JPG and PNG images to WebP — all inside your browser, with no upload step. .webp
- SVG compressor Shrink SVG files by stripping editor metadata and redundant markup. Optimization runs locally in your browser with a safety pass that removes scripts and external references before the file is ever rendered. .svg
Archives
- ZIP compressor Bundle files into a ZIP archive, open an existing ZIP to get its contents back, or repack an archive with stronger compression. Everything happens in your browser; your files never touch a server. .zip
- GZIP compressor Turn any file into a .gz archive — or open a .gz to recover the original — using the Compression Streams API built into your browser. No upload, no install, no account. .gz, .gzip, .tgz
- TAR compressor Bundle files into a POSIX .tar archive or unpack one to get its contents — entirely inside your browser, with no upload at any point. .tar
- ZSTD compressor Zstandard is the modern replacement for gzip: much faster at the same ratio. Compress any file to .zst or open one — all on your device. .zst, .zstd
- 7Z compressor 7-Zip’s LZMA compression is still one of the strongest around. Build or open .7z archives locally, with path-traversal and size protections. .7z
Office documents
- DOCX compressor A .docx is a ZIP package, and in image-heavy documents most of the weight is embedded pictures. This tool re-encodes those images and rebuilds the package — your text, styles and relationships are preserved byte-for-byte. .docx
- XLSX compressor Shrink heavy .xlsx workbooks by optimizing the embedded images inside the package. Formulas, cell styles and sheet data are left exactly as they are — the tool rebuilds the package around them, in your browser. .xlsx
- PPTX compressor Presentations are heavyweight because of photos, screenshots and media on the slides. This tool re-encodes embedded images and rebuilds the package — slide structure, themes and animations stay intact. .pptx
Spreadsheets & data
- XLS compressor Legacy .xls files are bloated and increasingly unsupported. Convert them to modern .xlsx (or CSV) locally — with clear warnings about what a converter cannot carry. .xls
- CSV compressor Switch your data between CSV and TSV with quoting rules intact, or gzip it for a much smaller transfer file. Processing happens in your browser — your data rows never touch a server. .csv
Audio
- MP3 audio inspector Find out what an .mp3 really contains before you use it: effective bitrate, duration, sample rate and channel count, read from the MPEG frame headers entirely on your device. .mp3
- WAV audio inspector Find out exactly what a .wav file contains before you work with it: duration, sample rate, channel count and bit depth, read from the RIFF header entirely on your device. .wav
Video
- MP4 video converter Convert MP4 to WebM (and back), trim a clip to a time range, or inspect its tracks — all processed by your own browser via WebCodecs and modern container tooling. .mp4, .m4v
- WebM video converter Convert WebM to MP4 (and back), trim a clip, or inspect its tracks — processed entirely on your device by your own browser. .webm
Developer & data
- JSON compressor Strip whitespace from JSON without changing a single value, then optionally gzip it. Your API responses, config files and datasets are processed entirely in your browser. .json
- HTML compressor Reduce HTML file size by trimming whitespace and redundant attribute quotes while preserving the document semantics. Inline scripts are never executed during processing, and nothing is uploaded. .html, .htm
- CSS compressor Shrink stylesheets with standards-based CSS minification, processed entirely in your browser. The browser-support profile is fixed at build time and documented — no surprises. .css
- JavaScript compressor Shrink JavaScript bundles and files with Terser-class minification, running entirely in your browser. Your source code is parsed and rewritten locally — it is never executed and never transmitted. .js, .mjs, .cjs
E-books
Fonts
- TTF font compressor Web fonts carry thousands of glyphs you never use. Subsetting keeps exactly the characters you need — the same HarfBuzz engine behind professional tooling, running in your browser. .ttf
- WOFF2 font compressor WOFF2 is already compressed — the real win is subsetting. Keep only the glyphs your pages use and serve a much smaller font, all processed on your device. .woff2