ImgTools is a free online image compressor that processes everything in your browser. Unlike most online compressors that upload your images to remote servers for processing, ImgTools uses the HTML5 Canvas API to compress images locally on your device.
This browser-based approach provides several advantages: complete privacy since your images never leave your device, instant processing without waiting for server uploads and downloads, no file size upload limits, and no dependency on internet connection speed for processing.
To compress an image, upload it to ImgTools, switch to the Compress tab, and adjust the quality slider. Lower quality produces smaller files. For most purposes, 75-85% quality provides excellent visual quality with significant file size reduction.
ImgTools outputs compressed images as JPEG, which provides the best compression for photographs. For images that need transparency, use the Convert tab to switch to WebP format instead.
The free tier allows 5 image operations per day. Pro users get unlimited access starting at $2.99/month.