pdfpix

Compress PDF to 250 KB

or drop one here
Compression level
Target size
Choose a PDF file first.

250 KB is 256,000 bytes, and that number is the reason the cap exists. It is a quarter of a binary megabyte, which is how the field was sized in the first place. The bench did not run a 250 KB target, so no hit rate on this page is measured for it.

How to compress a PDF to 250 KB

  1. Choose the PDF

    Press Choose a PDF, or drop the file on the page. The file is read in this tab and is not sent anywhere.

  2. The target is already set

    This page opens at 250 KB, so there is nothing to type. Pick a different level, or enter your own smaller number in KB, if you want another size.

  3. Press Compress

    Four methods race: copy the pages into a fresh file, re-encode the placed images, cut each embedded font down to the glyphs the pages draw, and, only when no other method reached the target, redraw the pages as images with the text kept on top.

  4. Read the check, then download

    Every candidate is opened again and its characters are counted against the source. The page shows the size, the method that won and the characters kept before it offers the download.

The four methods are described in full, with the measurements behind them, in how it works.

Why 250 KB is really 256,000 bytes

A 250 KB limit almost always started life as a quarter of a megabyte, which is 262,144 bytes if you count in binary all the way and 256,000 if you round the kilobyte and not the megabyte. Whoever wrote the form picked the round decimal label for the binary quantity underneath.

The compress tool uses 1,024 bytes to the kilobyte, so a 250 KB target here is 256,000 bytes and it stops below that. That reading matches how the caps are usually implemented, and it clears them.

What fits under 250 KB

One or two scanned pages at a quality where printed text stays sharp. A text document of any reasonable length, once its fonts are subset. What does not fit is a colour photograph at full resolution, or a scan running past six or seven pages.

The two measured targets either side of this were met on 18 of 38 cases at 200 KB and 9 of 16 at 500 KB. Reach rises with the cap, so expect something between those figures, with the kind of document mattering more than the exact number.

If it misses

You get the smallest file the engine could prove, together with the size it reached and the method that won. That is the information you need: a miss at 270 KB means one page or one quality step away, and a miss at 800 KB means the document has to change.

A 200 KB target is the next step down if the form turned out to be stricter, and a 300 KB target is the next step up if it turned out to be looser. Both use the same engine and the same checks.

Questions

Is a 250 KB limit 250,000 or 256,000 bytes?
Nearly always 256,000, because the cap started as a quarter of a megabyte and got a round decimal label. The tool counts the same way. If a form still refuses the file, it is doing plain decimal arithmetic, and 240 KB clears both.
How many scanned pages fit in 250 KB?
Two comfortably, three or four at a pinch. Past that the per page budget falls under 60 KB and small print starts to break up. Splitting the scan is better than pushing the quality lower.
Does the 250 KB target work on a phone?
Yes. Files this size are well inside what a phone browser handles, and the compression runs in the tab exactly as it does on a desktop. Nothing is uploaded from either.
What if I need 250 KB and the file is a text document?
Text documents are the harder case, because their weight is fonts and structure rather than pixels. Font subsetting is usually the winning method, and if it still misses, removing pages is the only lever left.

The other pdfpix tools

All 30 of them run in a browser tab like this one. Each reads its own output back and checks it before offering the download, and none of them needs an account.

Where to go next