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Compress PDF: Reduce PDF File Size

Compress PDF files and reduce their size to fit under email and upload limits. You see the new size before you download, and your file never leaves the browser.

or drop files here Processed on your device. Nothing is uploaded.

How to compress PDF

  1. Drop one or more PDFs into the box.

  2. Choose a level: Lossless, Balanced or Strong.

  3. Run it and compare the before and after size.

  4. Download the smaller PDF.

Reduce PDF size with the right level

Lossless rebuilds the file with tighter compression and drops unused objects. Nothing visible changes.

Balanced and Strong also re-encode large photos as JPEG and scale them down, to about 2000 px and 1400 px on the long side. Picture-heavy files shrink the most. If the result is not smaller, you keep the original.

Make a PDF smaller and keep text sharp

Only photos are touched. Text and vector graphics are never turned into images, so the compressed PDF stays searchable and prints cleanly. For more ways to cut size, read how to reduce PDF file size. Only need some of the pages? Delete the rest before you compress.

Guides

How to Reduce PDF File SizeHow to reduce PDF file size for email or upload: pick a compression level, see the before and after size, download. Free, runs in your browser.How to Combine PDF Files Into One DocumentHow to combine PDF files into one document for free: set the page order, merge in your browser and download. No upload, no signup, no watermark.How to Remove a Password From a PDFHow to remove a password from a PDF you can open: enter it once, save an unlocked copy. Free, runs in your browser, the file is never uploaded.How to Convert PNG to PDFHow to convert PNG to PDF: add your images, set the order and page size, download one PDF. Lossless, free, and nothing is uploaded.How to Make a PDF Searchable, Even a ScanHow to make a PDF searchable with free OCR: add a hidden text layer so scanned pages can be searched and copied. Runs in your browser.How to Convert Word to PDFHow to convert Word to PDF: use Save as PDF in Word, or turn DOCX files into PDFs in your browser for free. No signup, no upload, no watermark.How to Convert EPUB to PDFHow to convert EPUB to PDF: pick a page size and font size, convert in your browser, download. Free, no signup, and the ebook stays on your device.How to Attach a File to a PDFAttach a spreadsheet, image or any other file to a PDF in your browser. Free, no signup, and your files are never uploaded. Extract attachments too.How to Scan a Document on iPhoneHow to scan a document on iPhone with the Notes or Files app, save it as a PDF, then make it searchable and small enough to email.

Frequently asked questions

How do I compress a PDF for free?

Drop the PDF here, pick a level and run it. There is no signup, no watermark and no upload.

How much smaller will my PDF get?

It depends on the content. Files full of large photos shrink a lot on Balanced or Strong, while text-only files gain less because text is already compact.

Does compressing a PDF lower the quality?

Lossless does not change anything you can see. Balanced and Strong lower photo resolution, while text and vector graphics stay exactly as they were.

Why is my compressed PDF the same size?

Some files are already well compressed. When the result is not smaller, PDFDEN keeps your original instead of handing back a bigger file.

Can I compress several PDFs at once?

Yes. Drop multiple files and each one is compressed with the level you choose.

Is it safe to compress a confidential PDF?

The file is processed in your browser and never sent to a server. If it also needs a password, run Protect PDF afterwards.

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