Compress PDF
In your browser, no upload
at most the size you pick · text untouched
Specification
6 rows| Item | Value | Notes |
|---|---|---|
| Input | Read from the file itself, not its name | |
| Output | The same PDF, at most the size you pick | 500 KB, 1 MB, 2 MB, 5 MB, 10 MB, 20 MB, 25 MB, 50 MB |
| Photos | JPEG, 300 → 100 dpi | Quality 85 down to 50: the least change that fits |
| Text and drawings | Untouched | Text, fonts, shapes, links and form fields are the file’s own bytes |
| File size | Whatever this device holds | The file is read in this tab; it is never sent anywhere |
| Processed in | This browser | Not sent to a server |
What happens
4What happens, and why
Drop a PDF and this page measures it first: every photo inside is saved at each of 6 steps, from 300 dpi at quality 85 down to 100 dpi at quality 50, and the whole file is added up at each one. Then it offers the sizes below the file’s own that some step reaches — 500 KB, 1 MB, 2 MB, 5 MB, 10 MB, 20 MB, 25 MB, 50 MB — and each button says the step it takes. Press one and the file is written. It comes out at most that size; if it comes out over after all, it is written again a step lower and the note says so. One megabyte here is 1,000,000 bytes, the smaller of the two readings, so “under 10 MB” holds however a site counts.
A PDF is big because of its pictures: a scan is a photograph per page, and a report carries the photos pasted into it. Only those are saved again, as JPEG, at a stated quality and at most at a stated resolution on the page. A photo with more than 1.25 times the pixels the step’s resolution needs, where the page draws it, is made smaller to that resolution. 300 dpi is print resolution; 150 is more than a screen shows a page at. A photo that would not come out at least 10% smaller is left as it was — saving it again would cost quality for nothing.
Everything else is carried over byte for byte: text and the fonts it is set in, lines and shapes, links, bookmarks, form fields, and the images that are drawn rather than photographed — charts, screenshots, logos, black-and-white scans — which JPEG would blur. So is anything in print colours (CMYK) or a spot colour, where a JPEG would change the colour. Objects nothing in the document uses are left out. The badge and a row per image say what happened to each.
If even the last step cannot reach a size, that size is not offered, and the page says how small the file can be made here. Nothing is uploaded: the file is read in this tab and the new one is written here.
FAQ
5Will it look worse
Only where it has to, and only in the photos. Each size takes the least change that fits it, and its button says which. Quality 85 at up to 300 dpi is hard to tell from the original on screen or on paper; quality 50 at 100 dpi shows when you zoom in. Text stays sharp at any zoom, because it is not a picture — it is the same text, in the same font, as before.
Why did it come out smaller than the size I picked
Because the file needed no more. When the lightest step already fits, the file is written at that step rather than made worse to fill the space — the button says so by naming 300 dpi and quality 85. And one megabyte here is 1,000,000 bytes; a computer that counts 1,048,576 shows the file about 5% smaller again.
Why is no size offered for my PDF
Because its size is not in photos this page saves again. A PDF of text is small already; one that is big without photos is big because of fonts, drawings or black-and-white scans, which this page does not change — changing them would change how the document looks or reads. The page says which of these it is before offering anything.
Can I still search and copy the text
Yes. The text is the same text in the same fonts, byte for byte, so searching, selecting, copying and reading aloud work as they did. Links, bookmarks and form fields are kept too.
Is the PDF uploaded
No. The browser reads the file from your disk and writes the new one on this page. There is no upload endpoint on this site, so there is nowhere for the file to go. Nothing about the document is logged either — this page does not know how many pages your file has.