Up to 80% smaller · 3 quality levels · Free

Compress PDF Online Free

Compress PDF files online for free. Choose from 3 compression levels to reduce file size by up to 80% without losing quality. No signup required.

Drop PDF here or click to select

Up to 100 MB · PDF files only

Processed locally in your browser

13,588 PDFs compressed this week
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How it works

Three simple steps

Step 01

Open your PDF

Load the PDF you want to compress using the editor, then click the Compress button in the toolbar.

Step 02

Choose compression level

Pick Low (best quality), Medium (balanced), or High (smallest size). An estimated output size is shown for each level.

Step 03

Download compressed PDF

The compression runs in your browser in seconds. Download your smaller PDF — the original stays untouched.

Features

Everything you need

3 compression levels

Low (quality 85, ~10-20% smaller), Medium (quality 55, ~30-50% smaller), and High (quality 25, ~50-80% smaller) — choose the right trade-off for your use case.

Image recompression

JPG and raw images embedded in the PDF are re-encoded at a lower quality level — the biggest factor in file size reduction.

Smart image downscaling

High compression also shrinks images larger than 1000px. Medium caps at 1500px. This further reduces file size with minimal visible impact.

Metadata strip (High)

High compression removes document metadata (title, author, producer) that adds unnecessary bytes — safe for most sharing scenarios.

No quality loss for text-only PDFs

If your PDF contains no images, compression focuses on structure optimisation. Text quality is always preserved perfectly.

Before/after comparison

After compression, see the original and compressed file sizes side-by-side with the percentage reduction clearly highlighted.

FAQ

Frequently asked questions

How much can I reduce a PDF file size?
It depends heavily on the content. Image-heavy PDFs can shrink by 50-80% at high compression. Text-only documents (like contracts) typically see only 5-15% reduction since there are no images to recompress.
Will compression affect text readability?
No. Text is never recompressed — only embedded images are re-encoded. Fonts and vector graphics retain their full sharpness regardless of the compression level chosen.
What compression level should I use?
Use Low for documents you'll print (max quality). Use Medium for email attachments — good balance of size and quality. Use High for web upload or long-term archiving where file size matters most.
Does compression change the visible appearance of the PDF?
At Low and Medium levels, the visual difference is barely noticeable on screen. At High compression, heavily photographic images may show slight JPG artefacts, but text and diagrams look the same.
Is the compression lossless or lossy?
Image compression is lossy (JPG re-encoding). Structure compression (object streams, metadata removal) is lossless. The trade-off between size and quality is what the three levels control.

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