PDF Tools
Compress PDF files online for free and reduce PDF file size while maintaining the best practical balance between quality and file size.
Max upload 100MB · Automatic cleanup after 60 minutes
Drag & drop your PDF file here
or click to browse files
Supports PDF files up to 100 MB
How it works
PDF files can be large because they often contain images, fonts, embedded resources and other file data. Compression optimizes these elements to reduce PDF file size while maintaining practical quality.
25 MB
Original PDF
2 MB
Compressed PDF
Max 100 MB
OneFileKit Compress PDF reduces PDF file size for email, uploads and sharing. Choose Basic, Strong or Maximum compression depending on how much quality you are willing to trade for a smaller file.
Results vary by document. Image-heavy or scanned PDFs usually shrink more than already-optimized text PDFs. We do not promise a fixed compression percentage — the goal is a practical balance between quality and size.
Upload your PDF to OneFileKit, choose your preferred compression level, start the compression, and download the smaller PDF when processing is complete. No additional desktop software is required.
You can reduce PDF file size by compressing images and optimizing other elements within the document. OneFileKit provides multiple compression levels so you can choose the balance between file size and visual quality that suits your document.
Yes. You can use OneFileKit to compress PDF files online for free without installing dedicated PDF compression software.
It can. The amount of quality change depends on the PDF contents and the compression level you select. Basic compression prioritizes visual quality, while stronger compression can produce a smaller file with greater image compression.
Choose Basic when visual quality is most important, Strong when you want a balance between quality and file size, and Maximum when reducing the PDF to the smallest practical size is your priority.
PDFs can become large because of high-resolution images, scanned pages, embedded fonts, graphics, and other document resources. Image-heavy and scanned PDFs can often have more opportunities for file-size reduction than already optimized text-based PDFs.
Yes, scanned PDFs can be compressed. Because scanned documents often contain page images, reducing or optimizing those images can decrease file size. The final reduction depends on the scan quality, resolution, and existing compression.
Yes. OneFileKit works through your web browser, allowing you to upload, compress, and download a PDF without installing separate desktop compression software.
OneFileKit currently supports PDF uploads up to 100 MB on the Compress PDF tool. Files larger than the supported limit must be reduced or handled differently before uploading.
OneFileKit processes uploaded PDFs using private file handling and does not place them in publicly accessible directories. Uploaded and compressed files are automatically deleted after 60 minutes, provided that this matches your current production retention policy.
Your files are safe with us. We prioritize your privacy and data security at every step of compression.
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