File compressors
Compress
Pick a tool, drop your file in, and grab the result. Files are gone within an hour.
What the compressors do
Compress JPG, PNG and WebP keep the file type and follow the quality slider, which starts at 75. JPG is saved with mozjpeg and WebP with its slowest, most thorough encoder setting. Below 95, Compress PNG runs pngquant, which reduces the image to a palette of at most 256 colors, fewer as the slider goes down. From 95 up that step is skipped and the PNG is only packed more tightly. When the first result isn't smaller than your file, these three try a few lower qualities, down to 12, except for a PNG at 95 or higher.
Compress GIF encodes the animation again with ffmpeg at 15, 12 or 8 frames per second with a palette of 192, 128 or 64 colors, depending on the slider. Compress SVG removes comments and extra whitespace and leaves the shapes alone.
Compress PDF runs Ghostscript with its ebook setting first and its screen setting second, and keeps the first result that is smaller than your file. When neither is, you get an error instead of a bigger PDF. Compress DOCX, PPTX and XLSX unpack the file, save the JPG, PNG and WebP pictures inside again at a lower quality when that makes them smaller, and pack everything back together, so text, slides and formulas stay as they were.
Compress MP4 encodes the video as H.264 at 1200, 800 or 500 kbps with AAC sound at 128, 96 or 64 kbps. Compress MP3 and Compress WAV both give you an MP3 at 160, 96 or 64 kbps. ZIP packs files into one archive at the highest compression level, and Unzip unpacks an archive on the server and hands the files back in a new ZIP, because a download is always a single file.
Frequently asked questions
Why is my compressed file not much smaller?
Some files have little left to remove. A PDF that is mostly text, an office file without pictures or an SVG that was already written compactly barely changes, and a PNG at 95 or higher keeps all its colors on purpose. Compress PDF returns an error rather than a larger file.
Does Compress PNG change the colors?
Below 95 on the slider it does. pngquant turns the image into a palette of at most 256 colors, fewer as the slider goes down, which suits screenshots and graphics better than photos. From 95 up the palette step is skipped, so no colors are merged.
What is the size limit?
Without a plan a file can be up to 50 MB, and Compress MP4 takes videos up to 10 MB. Basic and Pro plans allow bigger files, and Pro also raises the video limit. For ZIP, all the files you add count together.
Can I choose the PDF compression level?
No. Compress PDF always tries the ebook setting of Ghostscript first and only uses the stronger screen setting when ebook doesn't make the file smaller. Scanned pages lose sharpness, most of all with the screen setting, so check the result before you delete the original.