Compress PDF

Reduce your PDF file size instantly — free, private, and entirely in your browser. Choose Standard mode for lossless optimization or Image Mode for maximum compression on scanned documents. Nothing is uploaded to any server.

    How it works

    1. Step 1

      Upload your PDF

      Drop a PDF onto the page or click to browse. It's opened locally in your browser — nothing is uploaded to any server.

    2. Step 2

      Choose a compression mode

      Standard mode restructures the PDF losslessly for modest size reduction while keeping text selectable. Image Mode re-encodes every page as a JPEG — great for scanned documents, with much larger reductions.

    3. Step 3

      Download the smaller PDF

      Click Compress PDF and your optimized file downloads instantly. The original file never leaves your device.

    Frequently asked questions

    How much smaller will my PDF get?

    It depends on the PDF. Standard mode typically reduces size by 5–30% for PDFs with redundant metadata or uncompressed object streams. Image Mode can achieve 50–80% reductions for scanned documents or image-heavy PDFs, but may increase the size of text-only PDFs since it converts vector content to rasters.

    What is the difference between Standard and Image Mode?

    Standard mode is lossless — it restructures the PDF's internal objects without touching page content. Text stays selectable, images keep their original quality, and the reduction is modest. Image Mode renders every page to a JPEG image and rebuilds the PDF from those images. It can achieve large reductions for scanned PDFs, but all text becomes unselectable and the quality depends on the JPEG setting you choose.

    Will my text still be selectable after compression?

    Yes in Standard mode — it never modifies page content. No in Image Mode — every page is converted to a JPEG image, so text is no longer selectable or searchable in the output PDF.

    Are my files uploaded to a server?

    No. PDFMuse compresses your PDF entirely in your browser using your device's own processing. Your files never leave your device and are never stored anywhere.

    Why did my file get larger after using Image Mode?

    Image Mode is most effective for scanned documents and image-heavy PDFs. For PDFs that contain mostly vector text and graphics, converting to JPEG can actually increase the file size because efficient vector data is replaced with raster image data. Use Standard mode for text-heavy PDFs.

    Can I compress a password-protected PDF?

    No. Password-protected PDFs cannot be opened by the tool. Remove the password protection first (using the PDF owner's password in a compatible viewer), then compress.

    Is there a file size limit?

    There is no hard limit, but very large PDFs (100 MB+) may be slow or run out of memory in Image Mode, especially on mobile. Standard mode handles large files more reliably since it does not render pages.

    Why PDF file size matters

    A PDF that looks perfect on your screen can become a problem when you try to share it. Email services typically cap attachments at 10–25 MB. Document upload portals — insurance forms, loan applications, university submissions — often impose even stricter limits. File storage quotas fill up with PDFs that accumulate over years of saving everything at maximum quality. And on a slow connection, a large PDF can take a frustrating amount of time to upload or open on the other end.

    Compression is the practical fix. Getting a PDF from 20 MB down to 4 MB means it fits in an email, loads faster when shared via a link, and takes up less space whether it lives locally or in the cloud.

    What makes a PDF large

    Not all PDFs are large for the same reason, which is why understanding your file helps you choose the right compression mode.

    Standard mode: lossless optimization

    Standard mode restructures the PDF's internal objects to use compressed streams and remove redundant metadata. It never touches the page content — text stays selectable and searchable, images keep their original quality, fonts remain fully embedded.

    Expect 5–30% reduction for most documents. Well-optimized PDFs already generated by modern tools may see little or no reduction. Text-heavy PDFs created by word processors typically benefit more from Standard mode than from Image Mode.

    Use Standard mode when:

    Image Mode: raster re-encoding for scanned documents

    Image Mode takes a different approach. It renders each page to a canvas at a fixed resolution, then re-encodes the result as a JPEG at your chosen quality setting. The resulting PDF contains a JPEG image of each page instead of the original content.

    This approach can reduce scanned documents by 50–80%. A 50 MB scan can come out at 5–15 MB, depending on the quality preset. The tradeoff is significant: text is no longer selectable or searchable in the output, because the vector text has been replaced by a raster image. If the PDF contains forms, annotations, or searchable text you rely on, Standard mode is the better choice.

    Choosing a quality preset

    When Image Mode makes the file larger

    Image Mode can increase the size of PDFs that contain mostly vector content — text, diagrams, and charts. A digital contract created in a word processor is efficiently stored as text plus layout instructions. Converting that to a JPEG image of the text is a much less efficient representation. If you apply Image Mode to a digital PDF and the file gets larger, switch to Standard mode instead.

    Typical results by PDF type

    PDF type Recommended mode Typical reduction
    Scanned documentImage Mode50–80%
    Image-heavy PDFImage Mode30–60%
    Digital text documentStandard5–20%
    Presentation with imagesStandard or Image Mode10–50%
    Already-optimized PDFStandard0–10%

    Using Compress PDF as part of a larger workflow

    Compression works best as a final step. Use Merge PDF or Split PDF to assemble the right set of pages first, then compress the result. Compressing pages you're about to remove wastes time and processing.

    If you want to reduce file size by removing content rather than re-encoding it, Remove Pages can be more effective than compression when the heaviest pages are ones you don't need. A 100-page scanned document where you only need 20 pages will shrink far more from removing 80 pages than from any compression setting.