Compress PDF to 300KB

To compress a PDF to 300KB, add it below and click Compress: Target size is already set to 300 KB. That works for most short documents: in our tests a 12-page scan came out at 175 KB. A long scan may not fit, and the tool tells you when it can't reach 300 KB rather than ruining the pages. Nothing is uploaded.

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How to compress a PDF to 300KB

  1. Click Choose PDF files or drop the PDF on the box.
  2. Leave Target size at 300 KB, or type a smaller number if your form asks for one.
  3. Click Compress. If the result is marked under target, click Download.
  4. If it says it couldn't reach your target, read the options under the result (below we explain what they do).
The compress tool with Target size 300 KB, showing a 36-page scan reduced from 27.19 MB to 522 KB with a message that it could not reach the target
This page's tool with the 300 KB target already set: a 36-page scan stopped at 522 KB, with the tool's explanation and options. October 22, 2026.

What we measured

We ran the live tool on October 22, 2026 (PT) in Google Chrome 155 on Linux, with sample files we made for the test. Target size was 300 KB with the default Recommended level. "As images" is the Convert pages to images option.

Sample PDFOriginalWith 300 KB targetAs images, 300 KB target
10-page text report11.4 KB9.0 KBOriginal kept (images would be bigger)
5 slides with pictures3.25 MB255 KB; pictures about 230 dpi292 KB
8 pages of photos (2400×1600 each)13.57 MB168 KB; photos about 144 dpi on the page283 KB
12-page scanned letter (200 dpi grey)9.06 MB175 KB; scan now 50 dpi276 KB, 54 dpi
36-page scanned document27.19 MB522 KB: target not reached385 KB: still not reached

The 12-page scan gave the same 175 KB in iPhone 13 emulation. Note that "as images" was not smaller here for most files: at 300 KB the normal mode had already pushed the images further.

Two crops of the same scanned page, the original at 200 dpi and the 300 KB version at 50 dpi; the heading is readable but the small body text is blurred
Top: the original scan. Bottom: after compressing to 300 KB (50 dpi). The heading is readable; the small print is blurry.

Is 300 KB realistic for your file?

From our tests: a few pages of photos or slides fit comfortably. Around a dozen scanned pages fit, but small print gets hard to read. A scan of about three dozen pages didn't fit at all, and the tool stopped at about 40–50 dpi rather than go lower, because the pages would be unreadable. Before you upload a 300 KB scan, zoom in and check that the numbers you need can still be read.

When it says "We couldn't reach your target size"

Privacy

The work happens in your browser tab, so your files aren't uploaded. The site counts page visits and sends one anonymous event per use (tool name, whether it worked, a file-size range). No event is sent when Global Privacy Control or Do Not Track is on. See the privacy policy.

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Frequently asked questions

Why can't my PDF get under 300KB?

Usually because it has many scanned pages. Each page needs some minimum detail to stay readable; in our test a 36-page scan stopped at 522 KB (385 KB as images). Split it or send fewer pages.

Will the text be readable at 300KB?

For photos, slides and text PDFs, yes. A 12-page scan was reduced to 50 dpi: headings stayed readable but small print was blurry. Zoom in and check before you upload.

Should I use Convert pages to images?

Only if the normal result is still too big. It can help with scans, but text becomes unselectable, and at 300 KB it was not smaller for most of our files.

Is 300KB 300,000 bytes?

The tool aims for 300 × 1024 = 307,200 bytes. If a site counts 300,000 bytes, set the target to 290 KB.

Full guide: How to Compress a PDF (and Why Some PDFs Won't Shrink) →