PDF Compressor
FreeReduce PDF file sizes while preserving readability. Choose your compression level.
Reduce the size of a PDF directly in your browser by choosing the compression level that best matches your needs.
PDF compression can be useful when a document is too large to upload, attach to an email, store efficiently or share through a platform with file-size limits.
The amount of space saved depends on what is inside the PDF. Image-heavy documents often have more room for reduction, while PDFs that are already optimized or mostly contain text may shrink only slightly.
Input
Drop a PDF to compress
Drag & drop or browse files
PDF only · Max 100 MB
Max size: 100 MB
Settings
Compression Level
Image-heavy PDFs benefit most. Text-only PDFs may already be optimised and can return 0% savings.
Result
No output yet
Upload a PDF and choose a compression level
How it works
Upload your PDF
Upload a PDF file up to 100 MB.
Choose compression level
Choose Low, Medium or High compression depending on how strongly you want to reduce image data and how much visual quality you want to preserve.
Download compressed PDF
Compress the PDF, compare the resulting file size and download the new document if the result suits your needs.
Why use this tool?
Three compression levels
Choose Low, Medium or High compression depending on whether you prefer lighter reduction or a smaller file with stronger image processing.
Compare file sizes
Check the original and compressed file sizes so you can see how much space was actually saved before downloading the result.
Useful for image-heavy PDFs
Scanned documents, photo-based reports and other image-heavy PDFs often have more room for compression than already-optimized or mostly text-based files.
Compress in your browser
The PDF is processed locally in your browser, so it does not need to be uploaded to a server just to create the compressed version.
When Should You Compress a PDF?
Email attachments
Compress a PDF when the original file is too large for an email service or when you want to reduce the size before attaching it.
Online forms and portals
Reduce PDF size when a job application, school portal, government site or other upload form has a maximum file-size requirement.
Scanned documents
Image-heavy scans can create large PDFs. Compression may reduce their size substantially, depending on scan resolution and image content.
Storage and sharing
Compress large reports, manuals or archived PDFs when smaller files are easier to store, transfer or share.
Understanding PDF Compression and File Size
A PDF can contain text, fonts, images, vector graphics, metadata and other document data. The amount of compression available depends on which of those elements are using the most space.
Image-heavy PDFs often have more room for reduction because photographs and scans can be re-encoded or downsampled. A text-heavy PDF that is already optimized may have very little unnecessary data left to remove.
Compression does not guarantee a particular percentage reduction. Two PDFs with the same original file size can produce very different results because their internal content is different.
Choosing Low, Medium or High Compression
Low compression
Use Low when preserving image detail matters more than achieving the smallest possible file.
This is a good starting point for documents containing photographs, diagrams or scans that still need to look clear.
Medium compression
Use Medium when you want a stronger reduction while keeping a practical balance between file size and image quality.
For many general-purpose PDFs, this is a sensible setting to try first.
High compression
Use High when reducing file size is the priority and some loss of image detail is acceptable.
Check photographs, scanned text and small graphics carefully because stronger compression or downscaling can make them less clear.
The best setting depends on the document. Always inspect the result rather than assuming High is automatically better.
Why Some PDFs Compress More Than Others
Image-heavy PDFs:
PDFs created from scans, photos or screenshots often contain large raster images and may offer more opportunities for size reduction.
Text-heavy PDFs:
PDFs containing mostly text and vector content may already be compact and can show much smaller savings.
Already-compressed PDFs:
A PDF that has already been optimized or compressed may not shrink much further.
High-resolution scans:
Documents scanned at very high resolution can be large because each page contains more image data. Reducing image resolution may lower file size, but it can also reduce fine detail.
PDF Compression vs Other PDF Tasks
PDF Compressor:
Use PDF Compressor when your goal is to reduce the size of an existing PDF.
PDF Merger:
Use PDF Merger when you want to combine multiple PDF files into one document.
PDF Splitter:
Use PDF Splitter when you want to extract pages or divide one PDF into smaller files.
PDF to Image:
Use PDF to Image when you want PDF pages exported as image files rather than a compressed PDF.
Supported PDF Limits and Requirements
Supported file type: PDF
Maximum upload size: 100 MB per PDF
Compression levels: Low, Medium and High
Compression is performed locally in the browser.