Read the limit before you touch the photo
Most rejections state the maximum in KB or MB, and the number in the error message is the one that counts. Forms sometimes mention pixel dimensions as well, and a file can fail for either reason, so note both before you start changing anything.
If no message appears, check the upload instructions or the help page for the portal. Knowing whether the ceiling is 200 KB or 2 MB changes the approach entirely, because a photograph from a camera can sit well above both.
Check the current size of the photo
Open the file details on your device and read the size, then compare it with the limit. The gap tells you how aggressive the reduction has to be: a photo that is slightly over needs a light pass, while one many times over needs fewer pixels as well.
Check the dimensions too. Some sites reject a file on pixel count even when the bytes are acceptable, and a large photo can be brought down in size and pixels in two quick steps.
Compress to just under the maximum
Open the compressor, choose the photo, and enter the limit as your target in KB or MB, or use the 200 KB preset when that matches the requirement. The tool searches for a JPEG at or below that maximum and verifies the finished file before it reports success.
It does not promise an exactly matching size, so read the output number on the result screen. If the target is very tight for a detailed image, the tool may also reduce pixel dimensions to get under it, which is usually fine for an upload.
- Enter the site limit as the maximum size
- Use the 200 KB preset when that is the stated cap
- Check the reported output size before downloading
- Resize first if the target is far below the original
Watch for transparency and format changes
The compressor always writes a JPEG, so a PNG logo with a transparent background comes back with a white background instead. If transparency matters, keep the original PNG and reduce the image by other means, or accept the filled background before you upload.
JPEG output suits photographs and screenshots, which is what most upload forms expect. When a portal explicitly asks for PNG or WebP, convert the compressed result afterward so the file matches the stated format exactly.
Work through a folder one image at a time
There is no batch compression here, so a folder of photos means repeating the same short pass for each file. Choose an image, enter the target, generate, and download, then move to the next one.
That rhythm is quick once the target is set, and it has a useful side effect: you see every result. Files that come out surprisingly small or still look heavy stand out immediately, and you can adjust the target for the rest of the batch.