Reduce image size in KB
When a form says keep it under 100 KB or your photo must be 50 KB, you need to reduce the size measured in kilobytes, not pixels. The compress tool below lets you type a KB target and lands the file at or under it.
Drop images here or click to upload
PNG, JPG, WebP, GIF, AVIF, HEIC — up to 50MB each
- Files never leave your device
- Runs in your browser
- Free, no signup
What reducing size in KB really means
File size in KB is about how many bytes the image takes up, which is separate from its pixel dimensions. A small photo can still be a big file, and a large photo can be a small file, depending on detail and compression.
The lever that controls KB for a photo is JPG quality. Lowering it throws away detail your eye barely notices and shrinks the byte count. Compress to an exact size and the tool sets that dial for you to hit a chosen KB.
Reduce KB without wrecking the picture
If the target is tight and the photo looks soft, the usual fix is fewer pixels. Resize the image smaller first, then reduce the KB, so the same byte budget covers a smaller, cleaner picture.
For a gentler trim that keeps quality high, compress the JPEG with the quality slider instead of forcing a hard KB cap. Either way, the whole process runs in your browser and nothing is uploaded.