Compress Image to 100 KB – Reduce Photo Size Online

A limit of 100 KB leaves about five times as much room as 20 KB. That is enough for a clear picture at a normal size on a phone or a laptop screen, which is why so many upload forms and listing sites ask for it.

A modern phone photo is often several megabytes, so it still has to shrink to a small fraction of its size. The tool aims to stay close to your limit instead of going far below it, because every kilobyte you give up costs quality for no reason.

The same limit gives different results depending on what is in the picture. As a rough guide:

• Phone photos usually need both a lower quality and fewer pixels. The longer side often ends up at about a thousand pixels or a little more, but this varies from picture to picture.
• Screenshots with flat colours and sharp edges often fit with little loss, especially when saved as WebP or JPG.
• Scanned pages need enough resolution to keep small text readable, so look closely at the result before you use it.
• Pictures with fine texture, such as leaves, fabric or a crowd, take far more space than a photo with a plain background.

• Crop first, so none of your 100 KB is spent on parts of the picture you do not need.
• If your form gives a size in pixels, set that with the Resize Image tool before you compress.
• Choose JPG under Save as when the website needs JPG, and WebP when it accepts it, because WebP is often a little smaller at the same quality.
• Start from your original file each time. Saving a JPG again and again removes more detail every round.

This tool counts 1 KB as 1,024 bytes, so 100 KB here is 102,400 bytes. Some websites count 1 KB as 1,000 bytes and would see that file as slightly over 100 KB. If yours ends up very close to the limit, enter 97 KB instead to leave a margin.

Always follow the size, the file type and the pixel dimensions in the official notice for your form. They differ between forms and can change, so this page cannot tell you what yours needs.