Large images slow down websites. These free tools compress images by 30-70% with no visible quality loss.

ImageOptim (Mac)

Drag and drop images to strip metadata, compress PNGs and JPEGs, and optimize for web. The gold standard for Mac image compression. Free and open-source.

Squoosh (Web)

Google’s web-based image compressor at squoosh.app. Compares original and compressed side-by-side. Supports WebP, AVIF, MozJPEG, and more. No install needed.

TinyPNG (Web)

The classic online compressor at tinypng.com. Free for up to 20 images at a time, 5MB each. Excellent PNG and JPEG compression with a simple drag-and-drop interface.

When to Use Which

ToolBest ForPlatform
ImageOptimBulk local optimizationMac
SquooshQuality comparisonWeb
TinyPNGQuick one-offsWeb