Compress PDF

Compress PDF files online for free and reduce PDF file size.

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Compress PDF

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PDF only · Maximum 50 MB

Compression Level

Maximum Compression Smallest file size. Image quality may be reduced.

Strong Compression Significant size reduction with good visual quality.

Recommended Balanced PDF size and visual quality.

Quality Compression Good size reduction while preserving very good quality.

High Quality Prioritizes visual quality with limited compression.

What is PDF Compression?

Compress PDF with five quality levels designed to provide a smoother balance between file size and visual quality. Choose Maximum Compression for the smallest practical output, or High Quality when preserving visual quality is more important.

Which Compression Level Should I Choose?

Maximum Compression prioritizes the smallest file size. Strong Compression provides a more aggressive reduction with better quality than Maximum. Recommended is the balanced choice for most PDFs. Quality Compression aims for a smaller file while preserving very good visual quality. High Quality prioritizes visual quality and may provide limited size reduction.

How Much Can a PDF Be Compressed?

There is no fixed compression percentage for every PDF. Image-heavy PDFs can often shrink substantially, while already optimized or mostly text-based PDFs may show only a small reduction. In some cases, the processed PDF can be similar in size or even larger.

PDF File Limit

Compress PDF v1.0 accepts one PDF up to 50 MB per request.

Temporary File Processing

The uploaded PDF is used for temporary server-side processing. The original input is not overwritten, and temporary processing files are cleaned up according to the iToolsEra temporary-file processing policy.

When Should You Compress a PDF?

PDF compression is useful when a document is too large to upload, email or share conveniently. It can be especially helpful for image-heavy PDFs such as scanned documents, but the amount of reduction depends on what is already inside the PDF.

Helpful Guides

Learn how to use this tool for common real-world tasks.

PDF

How to Compress a PDF for an Online Application

Learn how to reduce a PDF file size for an online application while keeping text and important details readable. Check the size before uploading.

Read guide

Frequently Asked Questions

Upload your PDF, choose a compression level and click Compress PDF. After processing, review the resulting file size and download the compressed PDF.

Choose from Maximum Compression, Strong Compression, Recommended, Quality Compression or High Quality. Recommended is the best starting point for most PDFs.

Compression can reduce image resolution or recompress image data, so some quality loss is possible. The stronger profiles are more aggressive, while High Quality prioritizes visual quality.

No. Some PDFs are already optimized or contain mostly text and may show little reduction. In some cases, the compressed output can be similar in size or slightly larger.

Compress PDF v1.0 accepts one PDF up to 50 MB per request.

No. The original uploaded PDF is used as a temporary input and is not overwritten. The compressed PDF is generated as a separate file.

Yes. iToolsEra Compress PDF is available as a free online PDF tool.

No. Uploaded PDF files and generated temporary files are cleaned up according to the iToolsEra temporary-file processing policy.