PDF Medic OnlineCompress PDF to 100 KB
Make a PDF smaller than 100 KB for an upload form — the box below is already set.
Files never leave your device
How to Compress PDF to 100 KB
- Press Choose a PDF, or drop your file on the box above. The file is opened by your browser and stays on your device.
- Fit a size is already picked, with 95 in Must be under (KB). Change it only if your form gives a different limit.
- Press Compress PDF. You get the best of the four levels that comes in under 95 KB.
- Before you press Download, read the smallest text on the result at full size.
How much fits in 100 KB
In 100 KB you can usually send one scanned page, even a busy one, or two lighter pages. Our test files gave these results; yours depend on how much is printed on each page.
- A short scanned letter, about ten lines on A4: 69 KB at Best quality. It fits without losing much.
- A scanned A4 page about half full of text: about 93 KB at Small.
- A full A4 page of small print, scanned in colour: about 84 KB at Smallest. Two such pages need about 170 KB.
- A page with one detailed camera photo: about 94 KB at Small.
Can the person reading it still read it?
At 100 KB the tool often has to go down to Small or Smallest. On a full A4 page, Small keeps about 110 pixels per inch and Smallest about 75. Headings and normal text stay clear, but tiny print, faint stamps, and the digits in reference numbers are the first things to blur.
So check before you send: open the downloaded file, zoom to 100% or more, and read the smallest line, every number you typed on the form, and the signature. A file that passes the size check but can’t be read may be rejected later by the person who checks it.
Spending 100 KB well
Every page in the file shares the same 100 KB. One scanned page can use it all and look sharp; three pages each get a third and look rougher. So remove what the form did not ask for, like an empty back side or a cover page, with Split PDF before you compress.
Don’t be surprised if the result is far below 95 KB. The tool moves in four fixed steps, so if Balanced comes out at 128 KB, the next step, Small, may land at 42 KB. That is still the best of the four that fits. The main Compress PDF page lists exactly what each step does.
Why the box says 95
95 here is 97,280 bytes, because this tool counts 1 KB as 1,024 bytes. A website that counts 1 KB as 1,000 bytes sets its 100 KB limit at 100,000 bytes, and 97,280 is under that too. With 100 in the box you could get up to 102,400 bytes, which such a site would refuse.
Everything happens in your browser: your file is never uploaded to any server. You can check: once your file is open, turn on airplane mode — the tool still works.
Questions
Can I compress a PDF to 100 KB without losing quality?
Text and lines never lose quality, because they are not changed. Pictures and scans always lose some detail; how much depends on the level needed. A light page may fit at Best quality, while a full scanned page usually needs Small or Smallest.
How many scanned pages fit in 100 KB?
Usually one full page, or two pages with less on them. In our test a full page of small print came to about 84 KB at Smallest, so a second page like it will not fit.
The text looks blurry after compressing. What can I do?
Give each page more room: send fewer pages, or split the file and upload the pages separately if the form allows it. If you can scan again, place just the paper on a plain background so no space is spent on the table around it.
Why is my result only 42 KB when I asked for 95?
The level above it was too big. The tool tries four fixed levels from best to smallest and stops at the first that fits, so the result can land well under your number.
Is my file uploaded?
No. Compress PDF to 100 KB runs in your browser on your own device. The file is never sent to our server or anyone else. Once your file is open you can even turn on airplane mode.
Is it free?
Yes. No sign-up, no limits on how many files, and no watermark is added to your file.
Does it work on a phone?
Yes, in any modern browser on iPhone, Android, Mac, Windows or Linux. Very large files work best on a computer, because a phone browser has less memory.