Compress PDF to 100 KB
Set the limit, not a vague quality percentage. The tool tries lossless compression first, then finds the highest quality that still fits under 100 KB.
Select a PDF file
or drop it here — the file never leaves your device
Working…
100 KB is the tightest target most forms ask for
Of all the common upload limits, 100 KB is the one that fights back. It is roughly the size of a single medium-quality photograph, and application portals routinely ask for a whole document to fit inside it.
Whether your file gets there without damage depends almost entirely on one thing: was the PDF exported from software, or scanned from paper?
If it came from Word, Excel or Google Docs
You are in good shape. A text-only document of two or three pages is often already under 100 KB, and where it is not, stripping the metadata and rewriting the internal structure usually finishes the job with no visible change at all. The tool tries this lossless pass first and stops there if it works — your text stays sharp and still selectable.
If it is a scan or a photograph of a document
Be realistic. A scanned page holds far more raw data than 100 KB can carry, so reaching that number means throwing pixels away. One page will usually stay readable. Three or four pages squeezed into a shared 100 KB budget will not — each page ends up with about 25 KB, and small print starts to smear.
Two things help more than any compression setting:
- Rescan at 200 DPI instead of 600. Most people scan at the highest setting their app offers, which produces a file four to nine times larger than a form portal will ever need. 200 DPI is plenty for printed text.
- Scan in greyscale, not colour. A black-ink document gains nothing from colour channels, and dropping them typically takes 20–35% off the size before you compress anything.
What the tool is doing
Rather than guessing at a quality percentage, it searches. It renders your pages once, then repeatedly tests different quality and resolution settings — narrowing in on the highest quality that still lands under your limit. That is why the result is usually noticeably better than dragging a slider to "maximum compression" and hoping.
Everything happens inside your browser using your own device's processing power. The PDF is never uploaded, so there is nothing to delete afterwards and nothing sitting on a server. The longer guide explains the trade-offs in more detail.
Questions people actually ask
Can every PDF be compressed to 100 KB?
No, and any tool that promises otherwise is not being straight with you. A text document almost always makes it. A ten-page colour scan will not reach 100 KB while staying readable. When the file cannot get there, this tool gives you the smallest usable version and says so rather than silently handing back something illegible.
Is my file uploaded to a server?
No. The compression runs in your browser using JavaScript on your own device. The file never crosses the network, which is also why it works on documents you would not want to hand to a website in the first place.
Why does my text look blurry after compressing?
Because reaching a small target meant re-rendering the pages as images. Real text is stored as instructions and stays sharp at any size; an image of text does not. If the tool reports it used the lossless pass, your text is untouched. If it re-rendered, try a slightly larger target such as 200 KB and compare.
Will the text still be selectable and searchable?
Only if the lossless pass was enough. Once pages are re-rendered to hit an aggressive target, the text becomes part of the image and can no longer be selected or searched. The result screen tells you which of the two happened.
Does it work on a phone?
Yes, though large documents will be slower because the work happens on your own device. A scan of more than about twenty pages is better handled on a laptop.
Why do upload forms ask for exactly 100 KB?
100 KB is a round figure that comfortably holds one scanned page at moderate quality, which is why it turns up so often on government and admissions portals. It is normally a per-file ceiling, so a single certificate or photograph fits, while a multi-page scan rarely does.
My PDF will not go below 100 KB. What should I do?
Almost always the file contains a full-page scan or photograph. Two things work: scan again in greyscale rather than colour, which removes most of the data, or split the document and submit only the pages the form actually asks for. A pure-text PDF that still will not compress is carrying embedded fonts, and those cannot be stripped without breaking the document.
Is a 100 KB PDF still readable when printed?
A text document prints at full quality at any file size, because the text stays vector. A scan squeezed to 100 KB usually falls below print quality: it reads fine on screen and looks soft on paper. If the copy will be printed and checked by hand, choose 300 KB or 500 KB instead.