About Compress PDF
Compress PDF rewrites the file more tightly. Balanced and Strong resize embedded photos to the resolution of the page. Smallest goes further: when redrawing each page as an image produces a smaller file, that is the file you download, and the result says that text is no longer selectable. You see the exact before and after size. If the result would not be smaller, Utilhex tells you instead of handing back a larger file.
How to use Compress PDF
- Choose the PDF you want to compress.
- Pick a level. Lossless only repacks the page data. Balanced and Strong resize photos. Smallest redraws pages at about 72 DPI when that file is smaller.
- Select Compress PDF.
- Compare the original and compressed sizes, then download the result.
Examples
Photo-heavy reports and scans
Use Smallest. High-resolution photos and scans are redrawn at screen resolution, which is where most of the file size goes. Text in that file is not selectable.
Text-only documents
Files exported from word processors are often already compact. Expect a small change, not a dramatic one. Text stays selectable unless Smallest redraws the pages.
Limitations
- Balanced, Strong, and Smallest resize JPEG, RGB, and grayscale images, including images with transparency masks, down to the size they are drawn. CMYK and JPEG 2000 images stay as they are.
- Smallest redraws each page as a JPEG when that file is smaller. Text in that download is not selectable. PDFs longer than 200 pages are not redrawn.
- Keep the original if you still need print-quality images or copyable text.
- Encrypted PDFs must be unlocked before compression.
Privacy
This tool processes everything locally in your browser tab. Your input is not uploaded to Utilhex or any third party, and it is discarded when you close or reload the page. Read the privacy policy for details.
Frequently asked questions
Are my PDFs uploaded to a server?
No. The file is read and processed by JavaScript running in your browser tab. Utilhex never receives the document, and closing the tab discards it.
Why did my file barely shrink?
A PDF whose page data is already tightly packed, or whose pictures are already the size they appear on the page, has little left to remove. Text stays selectable. The large reductions on photo and scan files happen when you choose Smallest and it redraws the pages.
Can this reduce a PDF by 90%?
It can, when the file is mostly high-resolution photos or scans and you choose Smallest. Those pages are redrawn at about 72 DPI, so a camera photo keeps only a small fraction of its pixels. A text document will not shrink that much, and Utilhex shows the real size either way.
Will text remain selectable?
Balanced and Strong only recompress photos, so text stays selectable. Smallest redraws each page as an image when that produces a smaller file, and text in that download is not selectable. The result tells you when that happened.
Is compression reversible?
Lossless mode is. The other levels permanently reduce image detail in the output file, so keep your original if you may need full quality later.