File size & formats
How to compress an image to 20 KB, 50 KB, 100 KB or 200 KB
Online forms often set a strict file-size limit. Here’s how to hit it without ruining the image.
Pick the right format
JPEG and WebP can be made smaller by lowering quality; PNG can’t, because it is lossless. For a size limit, export photos as JPEG — the Compress to KB / MB tool does this automatically for PNG inputs.
Let the tool find the quality
Enter the limit, such as 100 KB, and the tool searches for the highest quality that fits. You see the exact file size before you download, so there are no surprises when you upload.
When quality alone isn’t enough
Very small limits such as 20 KB are often impossible at full camera resolution. Allow the tool to reduce the pixel dimensions, or resize first: a passport-style photo at 400 × 500 pixels fits comfortably under 50 KB.
KB means 1,024 bytes
Most forms treat 1 KB as 1,024 bytes. The tool uses the same definition, so a file shown as 99.8 KB is safely under a 100 KB limit.
Frequently asked questions
How do I reduce a photo to under 100 KB?
Open Compress to KB / MB, enter 100 KB and download. If it can’t reach the limit at the current size, tick “Allow pixel dimensions to shrink”.
Will compressing reduce quality?
Some quality is always lost with JPEG compression, but finding the highest quality that fits keeps the loss as small as possible.
Compress & convert
Compress to KB / MB
Search for an output at or below a real byte limit. Free, and your image never leaves your browser.
Open Compress to KB / MB