Free Online File & Media Compressors
Shrink JPG, PNG, WebP, HEIC, MP3 audio, and video file sizes up to 80% without visible loss of quality.
Free JPG Image Compressor
Reduce JPG file weight up to 80% while retaining quality.
Free PNG Image Compressor
Shrink PNGs with palette reduction (up to 256 colours), keeping transparency.
Free WebP Image Compressor
Fine-tune WebP compression for maximum PageSpeed ranking.
Free MP3 Audio Compressor
Reduce MP3 audio bitrate to shrink file size for attachments.
Free WAV Audio Compressor
Compress WAV tracks by optimizing sample rates and channels.
Free PDF Compressor
Shrink PDFs by re-compressing embedded images. Text stays selectable.
Free JPG Image Compressor
Reduce JPG file weight up to 80% while retaining quality.
Free PNG Image Compressor
Shrink PNGs with palette reduction (up to 256 colours), keeping transparency.
Free WebP Image Compressor
Fine-tune WebP compression for maximum PageSpeed ranking.
Free HEIC Photo Compressor
Turn iPhone HEIC photos into smaller JPEGs before sharing.
Free MP3 Audio Compressor
Reduce MP3 audio bitrate to shrink file size for attachments.
Free WAV Audio Compressor
Compress WAV tracks by optimizing sample rates and channels.
Free MP4 Video Compressor
Re-encode videos as smaller H.264 MP4 files in your browser.
Free CSS Code Minifier
Compress stylesheets to remove whitespace and speed up web pages.
Free JavaScript Minifier
Compress JS scripts and strip comments to reduce bundle sizes.
Free CSS Minifier & Optimizer
Compress stylesheets to remove whitespace and boost Core Web Vitals.
Free Online ZIP Extractor & Reader
Unpack and view .zip archives directly in your browser without software.
Free Files to ZIP Creator
Bundle multiple files and documents into a compressed .zip download.
Why Choose ConvertStuff Free Online File & Media Compressors?
No hidden subscriptions, no daily limits, and no paid tiers. Every conversion is completely free with no watermarks.
All files are processed in your browser memory via WebAssembly. Your documents and photos never leave your device.
Eliminate server upload delays. Conversions finish in under 2 seconds directly on your device CPU.
Background reading
Performance & SEO · 8 min read
AVIF vs WebP vs JPG: Which Image Format to Use for Faster Pages
How JPG, WebP and AVIF compress images, what the published size comparisons actually show, and how to serve all three so every browser gets the smallest file it can read.
Read the guideSecurity & Privacy · 6 min read
Security Risks of Cloud File Converters and Why Client-Side WebAssembly Protects Privacy
A technical audit on cloud converter storage risks, multi-tenant server exposure, and how browser WebAssembly processes files locally.
Read the guide