Read the limit carefully before touching anything
A limit is often two limits. Some forms cap the byte size, some cap the pixel dimensions, and many cap both and also restrict the accepted formats. Check the smallest edge and the largest edge you are allowed, and check whether the destination needs an exact ratio. A file that meets the size requirement but is 3000 pixels wide will still be rejected by a form with a maximum edge, and a platform that crops to square will decide the composition for you if you do not.
Resize before you compress
Bytes are spent per pixel, so halving the dimensions removes roughly four times the amount of detail the encoder has to represent, and lets you keep a much gentler quality setting. Compression alone can reach the same number, but it gets there by discarding fine detail everywhere, and it shows first on texture, hair, foliage, and small text. If you are well over the target, resize until you are modestly above it, then compress the rest of the way.
Land on the target, not under it
Encoders work in quality steps rather than a continuous byte count, so a stated target is best effort and the result rarely lands on exactly the requested number. Leave a margin: aiming a little under the limit is safer than aiming at it, because a receiving system may count the file differently than the tool does, and a copy that has been re-saved on the way can come in slightly larger. Check the reported size on the result itself rather than trusting the setting you typed in.
Repeat the step across a set
Doing this one photo at a time is the reason people stop halfway. If you have a batch to bring under the same ceiling, work through them in one pass and inspect the worst-looking result rather than the first. The batch page here takes several files at once, reports a size for each, and gives you back an archive, which is the practical shape for a folder of receipts, a set of product photos, or a term's worth of school forms.
Quick checklist
- Confirm whether the limit is bytes, pixels, format, or all three.
- Resize to a little above the target, then compress the remainder.
- Verify the reported size of the copy; do not trust the setting.
- For a set, run one pass and inspect the weakest result.
Try the related tool
Use the guide’s decision with a copy of your own image. The tool runs in this browser and leaves the original file unchanged.
Compress Image