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Compress a PDF to a Target Size

name a size in KB · the tool lowers quality until it fits · browser-only

Most compressors just "make it smaller" and leave you guessing. This one aims at a number: type the size you need — 100 KB for an upload field, 500 KB for email, whatever the form demands — and it re-renders the PDF at progressively lower quality until the result fits under your target. Everything happens in your browser; the file is never uploaded.

Drop PDF files here or click to select

One or many · each is compressed to the same target

    Quick pick:
    no files
    Ready.

    No PDF handy? The 5 MB sample is a good compression target. More free sample files.

    How it hits the target

    The tool works down a quality ladder. First it tries a quick lossless re-save — if your PDF is already close, that may be enough. If not, it rasterises the pages at successively lower resolutions (200 dpi, then 168, 144, 120…) and JPEG quality, stopping at the first setting whose output fits under your target. You get the highest-quality version that still meets the size, not the most crushed one.

    When a target simply isn't reachable

    Physics wins sometimes. A 40-page text document won't reach 50 KB without becoming unreadable, and a single high-detail scan has a floor. When that happens the tool doesn't silently hand you a file that's still over the limit and pretend it worked — it returns the smallest version it could make and tells you the actual size, so you can decide whether to raise the target, split the document, or accept the result. Honesty beats a false "done."

    Common size targets, and why

    FAQ

    How do I compress a PDF to a specific size?

    Drop the file in, type your target in KB (or tap a quick-pick), and click compress. The tool lowers quality step by step until the output is under that size, then hands you the result with the achieved size shown. No upload — it all runs locally.

    Will the text still be selectable afterwards?

    Only if the lossless re-save alone met your target. Once the tool rasterises to hit a smaller size, pages become images, so text is no longer selectable or searchable. If you need both small and selectable, raise the target or use the regular compress tool in its non-rasterising mode.

    Why did my file come back larger than the target?

    Because the target wasn't physically reachable without destroying legibility. The status message tells you the smallest size achieved — from there, raise the target a bit or split the document.

    Is the file uploaded to a server?

    Never. Compression runs in your browser via pdf.js and pdf-lib. See the privacy policy.