How to Compress a PDF (Free, In Your Browser)
Shrink a large PDF in seconds. No software, no upload, no watermark. A simple step-by-step guide to reducing PDF file size while keeping it readable.
A PDF that's too large to email or slow to upload is one of the most common file headaches, and it's almost always caused by high-resolution images embedded in the document. Compressing the PDF re-encodes those images and strips redundant data, often cutting the file size by half or more while keeping the text perfectly sharp.
You don't need Acrobat or any installed software to do this. The guide below uses our free PDF compressor, which runs entirely in your browser: your file never leaves your device, there's no sign-up, and the result has no watermark. The whole process takes under a minute.
This guide uses Compress PDF
Free, private and instant. Open it now and follow along with the steps below.
Follow these steps
Step 1: Open the PDF compressor
Head to the Compress PDF tool. It loads instantly and works on desktop and mobile, nothing to install and no account required.
Step 2: Add your PDF
Drag your PDF onto the upload area, or click to browse and select it. The file is loaded into your browser locally. It is never uploaded to a server.
Step 3: Choose a compression level
Pick how aggressively to compress. A balanced setting keeps the document crisp while cutting size significantly. A stronger setting shrinks it further for email, at a small cost to image detail.
Step 4: Compress the file
Click Compress and let the tool re-encode the images and streamline the file. You'll see the new size and how much smaller it is compared to the original.
Step 5: Download your smaller PDF
Download the compressed PDF straight to your device. It has no watermark and is ready to email, upload or archive. If it's still too large, run it again at a stronger level.
Tips & best practices
- Compression mostly targets images. A text-only PDF is already small and won't shrink much.
- Start with a balanced level and only go stronger if you still need a smaller file. That preserves the best readability.
- If you only need part of the document, split or extract the pages you need first: a shorter PDF is a smaller PDF.
- For scanned documents, running OCR first can help, but expect scanned pages (which are images) to stay larger than digital-text pages.
Related tools
Merge PDF
Combine multiple PDF files into a single document, drag to set the order, then download. Free, fast and entirely in your browser.
Split PDF
Break one PDF into several smaller files. Split every page out, or carve out custom page ranges. Free, fast and entirely in your browser.
PDF to Word
Turn a PDF into an editable Microsoft Word (.docx) document, text extracted into clean, editable paragraphs, entirely in your browser with no upload.
Image Compressor
Shrink JPG, PNG and WebP images without a visible quality drop. Set the quality yourself, or compress to an exact target size like 100 KB. Free, entirely in your browser.
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