The limit you’ll meet most often
“PDF only, maximum size 200 KB” sits under the upload button of a long list of application forms: jobs, admissions, scholarships, government services, bank and insurance paperwork. It leaves enough room for one page to stay sharp, which is probably why so many sites settled on it.
Here is what fit in our tests:
- A one-page certificate came out at 165 KB from a phone photo and 171 KB from a 300 DPI scan, both at about 140 DPI. That’s sharp: stamps, signatures and small print all read, and it prints well.
- Three pages photographed with a phone came out at 172 KB, at 90 DPI. Readable, small print a little soft.
- A five-page bank statement, scanned in colour fit at 151 KB, at the lowest readable setting. Every figure can be read, but the edges are rough.
- A four-page report from Word, with a photo on each page, came out at 145 KB with its text perfectly sharp.
So 200 KB is comfortable for one or two scanned pages, workable for three or four, and the bare minimum for five.
How we pick the quality
We try the quality settings from sharpest down and stop at the first one that fits. The result is the sharpest version under 200 KB that our steps can make, not one that’s been squeezed further than it needs to be. If your file is already under 200 KB, the page tells you before you start.
We also count 200 KB as 200,000 bytes, a little stricter than the 204,800 some sites use. A file that passes our check passes theirs.
When you scan, scan sensibly
If you’re scanning the paper yourself, you can save a step. Many scanners are set to 300 DPI or more in colour, which makes a one-page certificate over 1 MB. At 150 to 200 DPI it still looks sharp, starts much smaller, and comes out of this page with more detail left. A phone scanning app on its normal setting is fine: it’s the size, not the app, that we fix.
Several documents in one upload
Forms sometimes ask for “all educational certificates in a single PDF under 200 KB”. Do it in this order:
- Put them together with Merge PDF.
- Remove anything they didn’t ask for with Delete PDF pages.
- Compress the merged file here, once.
Compressing each one first means guessing a size for every part. Compressing once lets us find the best quality for the whole file. If the merged file can’t reach 200 KB, the result screen says so and offers to split it into parts under 200 KB instead.
Checked against the tool on 22 October 2026. How we write and test these guides