Online forms love size limits. A job portal wants your CV under 200 KB, an exam board wants the signed declaration under 100 KB, a scholarship site will not take anything over 50 KB, and a visa portal stops at 1 MB. A normal compressor makes a file smaller, but you cannot tell in advance whether it will be small enough. This tool works the other way round: you type the size you need, and it gives you the best-looking PDF that fits.
Type the target in kilobytes. The box starts at 100 KB, and you can choose anything from 10 KB up to 10 MB. The tool first rewrites the file without touching how it looks. If that is not enough, it re-saves the photos and scans inside the PDF, trying different quality levels and image sizes until it finds the highest quality that is still at or under your target. Text and lines are never turned into pictures, so they stay sharp and searchable even when the photos get lighter.
Sometimes a target is simply too small. A twenty-page scan cannot become 20 KB without becoming unreadable. When that happens, the tool does not pretend: it gives you the smallest file it could make, tells you its size, and suggests what saves more, such as removing pages you do not need or making a colour scan black and white. You then decide whether to try a different target.
All of this happens on your own device. The file is never uploaded, which is what you want for mark sheets, ID cards, salary slips and signed forms, the documents portals most often ask for. There is no sign-up, no watermark and no limit on how many times you try. Your original file is not changed; the new one ends with the target size in its name, like -100kb.
Which size should you choose? Use the number the portal states, or a little less if it says something like up to 100 KB. Remember that 1 MB is 1024 KB. For the smallest targets, one or two pages work best. If you do not have a fixed limit and just want a lighter file, the regular Compress PDF tool is quicker.