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PDF Compressor

Re-optimize and compress PDF files to reduce their file size.

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Drop PDF here or click to select

Shrink PDF File Size in Your Browser

The PDF Compressor re-optimizes a PDF so it takes up less disk space and is easier to email or upload. It works by re-saving the document with object streams enabled, which packs the internal PDF structure more efficiently and strips out redundant data and bloated cross-reference tables that many PDF generators leave behind.

This tool is ideal when a file is just over an attachment limit, when you want to speed up a slow upload, or when you need to store many documents without filling up storage. Because the optimization is structural rather than destructive, your text stays sharp and selectable and the page layout is preserved exactly as it was.

How to Compress a PDF

Drag a PDF onto the drop zone, or click it to browse for a file from your device. Compression begins automatically as soon as the file is loaded, so there is nothing else to configure.

When it finishes you will see three figures: the original size, the percentage reduction, and the new compressed size. Click "Download Compressed PDF" to save the optimized copy. The download is named with a "compressed_" prefix so you never overwrite your original by accident.

What to Expect From the Results

Savings vary a lot depending on how the PDF was created. Files exported by older software, scanners, or office suites often contain a lot of structural overhead and can shrink noticeably. Files that are already lean, or that are dominated by high-resolution scanned images, may only shrink a little, in which case the tool tells you the PDF is already well-optimized.

This is a lossless structural optimization: it does not re-encode or downsample images to force a smaller size, so you never trade away visual quality. If a file barely changes, that usually means it was already efficiently saved.

Frequently Asked Questions

Are my files uploaded to a server?▼
No. The entire compression runs locally in your browser using JavaScript. Your PDF is never transmitted anywhere, which makes it safe for confidential or sensitive documents.
How does the compression work?▼
It re-saves the PDF with object streams enabled, repacking the document's internal structure and removing redundant data and cross-reference bloat. It does not downsample images, so quality is preserved.
Why did my file barely get smaller?▼
If a PDF is already efficiently saved, or is mostly made up of large scanned images, there is little structural overhead left to remove. In that case the tool reports that the file is already well-optimized.
Will compression reduce the quality of my PDF?▼
No. This is a lossless optimization that leaves text and images untouched, so pages look identical to the original while taking up less space.
Is there a file size limit?▼
There is no fixed limit imposed by the tool, but because processing happens in your browser, very large files depend on your device's available memory. Most everyday documents process in a second or two.
Is the PDF Compressor free to use?▼
Yes, it is completely free with no signup, watermarks, or daily limits.

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