How to compress a photo to a KB limit without wrecking it
Application forms cap the file size, sometimes at 50 KB. The order matters: fix the pixel size first, then compress, and only then argue with the quality slider.
Why the obvious way fails
A form asks for a photo under 100 KB. You drag the quality slider down, the file lands at 140 KB, you drag further, and now the photo looks like it was faxed. The reason is that you are compressing a picture that is far bigger than it needs to be: a 12-megapixel phone photo carries about 4,000 × 3,000 pixels of detail that a 300-pixel-wide form field will never show.
Compression throws away quality. Resizing throws away pixels nobody was going to see. Do the second one first and you rarely need much of the first.
The order that works
- Read the form again and write down both numbers: the pixel size (or print size) and the KB cap. Many forms give only one of them; if it gives only KB, you choose the pixels.
- Resize to the pixel size the form asks for. If it asks for none, 600–1000 pixels on the long side is plenty for a photo that will be viewed on screen.
- Now compress to the KB cap. A photo at the right pixel size usually reaches 100 KB with quality still in the 70–85 range, which looks fine.
- Check the result at full size before you upload it. Text in a scanned document is the first thing to go.
When it still will not fit
If the file is stuck above the cap at the lowest usable quality, the format is often the problem. A photo saved as PNG barely shrinks at all, because PNG is lossless — the same picture as JPG is routinely five times smaller. Screenshots of text are the opposite case: they stay sharp and small as PNG and turn to mush as JPG.
A scan of a document that must stay readable is the hardest case. Reduce the pixel size in steps rather than crushing the quality, and stop as soon as the smallest text is still legible when you zoom to 100%.
Doing it in ToolMelo
Everything runs in your browser, so the photos are not uploaded anywhere, and 1 KB is counted as 1,000 bytes — the same way the forms count it.
- Open Crop & Resize Images if you need a specific pixel size, and export.
- Open Image Compressor, enter the KB cap in “Target size (KB)”, and compress. The pixel size does not change, and the badge tells you whether the result met the target.
- If it says it is over the limit, the advice under it names the reason — PNG that cannot shrink, or pixels that need reducing first.
- For a batch, both tools take up to 20 images and hand the whole set to the next tool.