Compress PDF to 100 KB
Get a PDF under 100 KB, as sharp as that size allows.
or drop files anywhere on this page
Your files stay in this browser. Nothing is uploaded.
About Compress PDF to 100 KB
This page is Compress PDF with its Target size set to 100 KB. Add a PDF and it tries its settings from gentle to strong until the file comes in under 100,000 bytes, then hands you the sharpest version that made it. The file is read and rewritten in this browser tab and is never uploaded.
100 KB is the tight end of upload limits. It holds a page or two of scans, and most typed documents are under it already, but a long scan will not fit. When a file cannot get there with its text still readable, the result says so, gives you the smallest version it made, and names what is taking the space.
How it works
- Add your PDF, or drop it anywhere on the page. You can add several; each one is fitted under 100 KB on its own.
- Target size is already set to 100 KB. If your form asks for something else, pick another size, or Custom size to type an exact limit such as 150 KB.
- Click Compress to 100 KB. It usually takes two or three tries, and for a short file that is well under a second.
- Read the note under the file name. It names the setting that was used, or says why the file could not fit.
- Download the result. If it did not fit, the result screen offers Split PDF and Delete pages to cut it down.
What fits in 100 KB
We ran five test files through this page: a scanned page and a phone photo of a page made from this site's own pages, a typed two-page document, a report with photos, and a ten-page scan. The results below are the files that came out.
| Test file | Before | Result |
|---|---|---|
| One scanned page | 543 KB | 76 KB, at 100 ppi and JPEG 65% |
| Phone photo of a page | 2.83 MB | 93 KB, at 144 ppi and JPEG 45% |
| Two-page typed document | 49 KB | Already under, returned unchanged |
| Seven-page report with two photos | 3.60 MB | Did not fit: 128 KB at the smallest |
| Ten scanned pages | 4.87 MB | Did not fit: 256 KB at the smallest |
Why long scans and reports miss 100 KB
A scanned page is a photograph of paper. Even at the strongest setting Target size uses, 72 ppi and JPEG 30%, each page of our ten-page scan still took about 26 KB, so 100 KB holds three scanned pages at most. A longer scan has to become several files: split it into parts of three pages or fewer, or delete the pages the form does not need.
The report missed for a different reason. Its two photos shrank to 63 KB between them, but its five typed pages carry about 65 KB of fonts and text, and no image setting touches those. For a file like that the result note says the text and fonts are the floor, so you know splitting, not another setting, is the way under.
Why it picks the sharpest setting, not the smallest
Target size stops at the first setting that fits, working from gentle to strong, so the file lands close to 100 KB rather than far below it. Our one-page scan came out at 76 KB at 100 ppi: the next setting up made 104 KB, just over. Squeezing it further would only have cost detail the form was willing to accept.
It never goes below 72 ppi at JPEG 30%. That is about where ordinary body text in a scan stops being readable, and a form that asks for a certificate is no use if the words on it cannot be read.
Frequently asked questions
Target size aims for 100,000 bytes or fewer, which is under 100 KB whichever way the site you upload to counts it. This site shows sizes in thousands of bytes too, so the size on the result screen matches the limit you chose.
Yes. Only the pictures inside the PDF are re-encoded. Typed text stays text, so it can still be searched, copied and read aloud by a screen reader, and it stays exactly as sharp as it was.
Some tools do, and the text stops being text: it can no longer be searched, copied or read by a screen reader. Target size only works on the pictures already in the file.
It comes back exactly as it was, and the note says so. Nothing is re-encoded, so nothing loses quality.
Yes: choose Custom size and type 50. In our tests a scanned page came out at 37 KB and a phone photo of a page at 44 KB. Two scanned pages take about 52 KB even at the strongest setting, and our two-page typed document was 49 KB to begin with, most of it fonts, so a longer one may not fit either.
Yes. Add them together and each one is fitted under 100 KB on its own, so a short file keeps more detail than a long one. The result lists every file with its own note, and a file that could not fit is marked so you can see which.
You still get the smallest version it could make, and the note says whether pictures or fonts are taking the space. Split PDF and Delete pages on the result screen open that smaller file, ready to cut down. For a scan, parts of three pages or fewer usually fit.
Other sizes
Related tools
This tool ran entirely in your browser and nothing was uploaded. Your Recent files list keeps a copy of local files under 5 MB until you clear it. How your files are handled.