The free PDF Compressor reduces the size of a PDF so it is easier to email, upload, or store. Upload your file and the tool re-encodes the images inside it at a lower size, producing a smaller PDF you can download.
Being straight about what compression does: it mainly works by reducing the size of images in the document, so a PDF full of high-resolution photos or scans can get dramatically smaller. A PDF that is already optimized, or one made almost entirely of plain text, has little image data to shrink, so the reduction may be small or occasionally none at all. If the compressed result would come out larger than what you uploaded, the tool returns your original file instead. The output file also carries a short branding note in its metadata, so a very small PDF can end up several hundred bytes larger than it started. The tool cannot shrink data that is already as small as it sensibly gets.
How to Compress a PDF
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Upload your PDF. Select the file or drag it onto the upload area.
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Compress. Pick a compression level (Recommended is selected by default), then click Compress PDF. The tool re-encodes the images to reduce the overall file size.
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Download. Save the smaller PDF to your device.
What Compression Can and Cannot Do
Compression trades some image detail for a smaller file. For documents with photos or scanned pages the size drop can be large, and how much quality you keep depends on the level you pick: Extreme gives the smallest file and the softest images. For a PDF that is already compressed, or a text-only document, there is little to remove, so do not expect a large reduction. Black-and-white scans vary: some shrink a lot, others barely change. If your goal is a specific small target and the file is mostly text, the size may already be close to its minimum.
What Happens to My File?
Your PDF is uploaded to our server and compressed there, not in your browser. Uploaded PDFs are deleted from our servers immediately after processing, whether it succeeds or fails. The result is stored under a random, unguessable web address and stays available to download for about two hours, then it is deleted automatically. Uploads and downloads go over HTTPS.
When to Compress a PDF
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Emailing a large file. Try to get under an attachment size limit without splitting the document.
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Uploading to a form. Bring a file closer to a size cap on a job application, government portal, or submission system.
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Saving storage. Shrink scanned documents that are taking up space.
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Faster sharing. Send a lighter file that downloads quickly for the recipient.
Related PDF Tools
Also useful: convert a PDF to grayscale (this can shrink color-heavy files further), merge PDFs before compressing a bundle, or repair a damaged PDF.
