How to Compress an Image to an Exact KB Size
"Compress to 20KB" sounds simple until you try it in a normal photo editor and end up dragging a quality slider up and down, exporting, checking the size, and repeating. There is a much faster way: use a tool that targets the exact size for you. Here is how, and how to keep the image looking good.
Why an exact size matters
Application forms do not care how "good" your photo looks — they enforce a hard kilobyte limit. Anything over it is rejected, and some forms reject anything under a minimum too. So the goal is not "smaller", it is "a specific number": at or just under the limit, with the best quality that fits.
Method 1 — a target-size compressor (fastest)
- Open the tool. imageto10kb runs in your browser — no app, no signup, and your image never leaves your device.
- Drop your photo. JPG, PNG or WebP all work.
- Type the size. Enter 10, 20 or 50 KB (or pick a preset). The tool automatically searches for the highest quality that stays under that number.
- Lock the dimensions if needed. If your form lists pixel dimensions, set them too.
- Download. Check the before/after preview and save the file.
Method 2 — on your phone
You do not need a desktop. Open imageto10kb in your mobile browser, choose the photo from your gallery, set the size, and download — it works the same on Android and iPhone. This is handy because most people take the photo on their phone in the first place.
Why not just use Paint, Preview or a quality slider?
You can, but you will be guessing. A "70% quality" export might be 90KB on one photo and 15KB on another, because file size depends on the image content, not just the quality setting. Targeting the size directly removes the trial and error.
Keeping quality high
- Start from the best original you have. Compression can only remove detail, not add it.
- Reduce dimensions before crushing quality. A smaller pixel size at higher quality often looks better than a large image at very low quality for the same file size.
- Use JPG for photos. It compresses photographs far more efficiently than PNG.
- Aim for the top of the allowed range so you are not throwing away quality you are allowed to keep.
💡 Remember: the target is a number, not "as small as possible". Hit the limit with room to spare and keep the picture sharp.