Compress a PDF on a Mac

To compress a PDF on a Mac, open it here in Safari or Chrome, pick Recommended or Strong (or tick Target size and type the size you need), click Compress and download the smaller copy. You choose how hard to compress, or the size you need, and see the old and new size before you save. Nothing is uploaded.

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Want to check that your file isn't uploaded? Compress without uploading: how to verify it yourself

How to compress a PDF on a Mac

  1. Drag the PDF from Finder onto this page, or click Choose PDF files. You can add several at once.
  2. Choose Low, Recommended or Strong, or tick Target size and enter a size in KB or MB.
  3. Click Compress. Each file shows its old size, new size and the percentage saved.
  4. Click Download. The file goes to your Downloads folder as name-compressed.pdf.
Compress PDF results: a 5-page slide deck from 3.25 MB to 490 KB and a 12-page scan from 9.06 MB to 2.40 MB on Recommended
Two test files on Recommended, October 22, 2026.

What we found when we tested it

We ran the live tool on October 22, 2026 (PT) in headless Google Chrome 155 on Linux, with sample files we made for the test. The sizes below are what the tool reported; your files will differ, because the saving depends on how many images are inside.

Test fileRecommendedStrong
5-page slide deck with photos, 3.25 MB490 KB (−85%)113 KB
8-page photo booklet, 13.57 MB1.72 MB365 KB
12-page scanned document, 9.06 MB2.40 MB (−74%)1015 KB
10-page text report, 11 KB9 KB9 KB

Text-only PDFs barely shrink because there are no images to recompress. Text stayed selectable in every result above.

Preview's built-in option

Every Mac can already do this in Preview: open the PDF, choose File > Export and pick Reduce File Size from the Quartz Filter menu, or tick options such as Optimize images for screen and Save images as JPEG. Apple notes the PDF may be of lower quality and that the size depends on the options you choose. Apple's guide doesn't describe a way to aim for a specific size such as 500 KB, which is where the target size here helps. We couldn't measure Preview's results ourselves because our test machine isn't a Mac, so we don't compare numbers here.

When it can't get small enough

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.

Related tools

Sources

Frequently asked questions

Is this better than Preview's Reduce File Size?

It gives you different controls: three levels or a target size, and the new size before you download. Preview is built in and works offline. We couldn't test Preview, so we don't claim one makes smaller files.

Does it work in Safari?

The tool runs in any current browser on a Mac. Our measurements were made in Chrome.

Will my text get blurry?

No. Only images are recompressed; text and fonts are copied as they are, unless you choose Convert pages to images.

Why did my PDF barely shrink?

It probably has few images, or its images use a format the tool doesn't re-encode, such as CMYK. Try Convert pages to images for scans.

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