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Compress PDF

Reduce PDF file size for email and upload limits. Choose lossless or strong compression. No upload.

Your files never leave your device

How to compress pdf

  1. 1

    Choose your PDF files

    Click the upload area or drag files onto it. Nothing is uploaded — files are opened locally.

  2. 2

    Adjust the settings

    Pick compression, then press the convert button.

  3. 3

    Download the result

    Save each file individually or everything at once as a ZIP.

Large scanned or image-heavy PDFs bounce off email limits and upload forms. Lossless mode repacks the file without touching its content; the stronger modes re-render each page as an optimised image, which shrinks scans dramatically but makes text unselectable. If a PDF can’t be made smaller, you get the original back.

Read the full guide with screenshots

What is PDF?

PDF (Portable Document Format) preserves a document’s layout on every device and operating system, which makes it the standard for sharing, printing and archiving.

Is it private?

Yes. Unlike upload-based converters, ZapMorph processes files inside your browser tab, so the file stays on your device. It is never transmitted, stored or logged — close the tab and it’s gone.

Frequently asked questions

Is the compress pdf converter free?

Yes. Convert 1 file a day without an account, or 5 files a day with a free account. Pro removes all daily limits.

Are my files uploaded to a server?

No. The conversion runs entirely in your browser, so your files never leave your device. We only count how many files you convert — never their names or contents.

What is the maximum file size?

Up to 25 MB per file without an account, 50 MB with a free account, and 1 GB on Pro. Very large files also depend on your device’s memory.

Can I convert multiple PDF files at once?

Yes. Select several PDF files at once — up to 5 on the free plan or 50 on Pro — and download all results in a single ZIP.

Does it work on Mac, Windows, iPhone and Android?

Yes. It works in any modern browser — Chrome, Edge, Firefox and Safari — on desktop and mobile, with nothing to install.

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