Stayput

Compress a PDF

Shrink PDFs for email or upload limits. Three levels, from lossless cleanup to aggressive. Processed on your device.

Nothing is uploaded Works offline Open source No limits, no watermark
Drop PDF files hereor click to choose files. Batches welcome.
    Working…

    Done

    Your files are processed on this device and never sent to a server. Reload the page to clear everything from memory.

    How it works

    1. Drop one or more PDFs.
    2. Pick a level. "Recompress images" is the default and keeps text selectable.
    3. Compare the before and after sizes and download.

    In your browser, not on a server

    Lossless cleanup rewrites the PDF with pdf-lib using object streams and deduplicated resources. Image recompression uses pdf.js to find embedded images, re-encodes each one at a lower quality on a canvas, and pdf-lib swaps the new streams in. Flatten renders every page to an image at the resolution you pick. Each mode runs entirely in your browser.

    Compared with upload-based tools: PDF compressors online are the most upload-hungry tools there are, because the whole document has to go up before anything happens. Here a 50 MB scan is processed without a single byte leaving your machine.

    Verify it yourself. Load this page, turn off Wi-Fi or switch to airplane mode, and run the tool. Or open your browser's developer tools (F12, or Cmd-Option-I on a Mac), pick the Network tab, and watch it while you convert. The panel above does the same count for you.

    Questions

    How does each level work?

    "Lossless cleanup" rewrites the file with compressed object streams and drops unused data; text and images stay identical. "Recompress images" additionally re-encodes embedded photos at a lower JPG quality and caps their resolution, which is where most of the savings come from in scanned or photo-heavy PDFs. "Flatten pages" renders each page to an image at the resolution you choose. It gives the smallest files for scans but text is no longer selectable.

    Why did my PDF barely shrink?

    PDFs made from text (Word exports, invoices) are already small and consist mostly of fonts and vector data that cannot be compressed further without losing content. Compression helps most on files with large photos or scans.

    Is the PDF uploaded to a server?

    No. Everything runs in your browser using pdf-lib and pdf.js. That is why there is no size limit and no queue.

    More PDF tools

    Merge PDF

    Combine PDFs into a single document. Drag to reorder. No file limits, no watermark, nothing uploaded.

    Split PDF

    Pull out the pages you need, or break a document into single pages. Done on your device.

    Rotate PDF

    Fix sideways scans for good. Rotate every page or just the ones you pick, then save.

    Image to PDF

    Turn photos, scans and screenshots into a single PDF. One image per page, in the order you choose.

    Popular conversions

    Guides