Compress PDF to Exact Size

Hit a precise KB or MB target for your PDF — pick a preset or enter a custom size. Runs entirely in your browser.

Compress a PDF to a target size

Upload a PDF, choose a target size, then download a PDF that fits it.

Drag & drop a PDF here, or click to browse
Works best on scanned or image-heavy PDFs.

    Result

    Original size
    0 KB
    Final size
    0 KB
    Target
    0 KB

    Your PDF is processed locally in this browser tab using pdf.js and pdf-lib. It is never uploaded to Calcooo or any server.

    How to use this tool

    1. Drag and drop your PDF into the box above, or click to browse and select it.
    2. Pick a quick preset (e.g. 500 KB) or enter a custom target size and unit.
    3. Press Compress to target — the tool searches across render scale and quality to find settings that fit your target.
    4. Click Download PDF to save the result, which will be at or as close as possible to your target size.

    FAQ

    Frequently asked questions

    Is my PDF uploaded anywhere?

    No. The target-size search runs locally in your browser using pdf.js and pdf-lib — your PDF is never uploaded to a server.

    How does hitting an exact size work?

    Each page is re-rendered as a JPEG image. The tool searches across render scale and JPEG quality to find settings that fit your target size, then rebuilds the PDF from those images.

    Will text stay selectable?

    No — pages become images in the process, so text is no longer selectable or searchable. This trade-off is what makes precise size control possible.

    Can every PDF reach a very small target like 20KB?

    Not always — a many-page PDF may not be able to reach a very small target without becoming unreadable. The tool will get as close as it reasonably can and tell you if it couldn't fully reach the target.