PDF Compressor

A PDF Compressor reduces the file size of a PDF document by applying compression algorithms to the embedded content — particularly images, which typically account for 80–95% of a PDF's file size. Smaller PDFs upload faster, email more easily, meet file size limits, and load quicker when shared as links — without necessarily sacrificing readable quality for the intended use case.

Why PDFs get large

PDFs can grow to surprisingly large sizes for several reasons:

High-resolution embedded images: A PDF created from a 24-megapixel phone camera photo embeds the full-resolution image. For screen viewing, that resolution is many times more than necessary.

Unoptimised scan output: Office scanners often output PDFs at 600 DPI with no compression, resulting in scan files of 5–10 MB per page. A single 10-page scanned contract can be 80–100 MB.

Repeated embedded fonts: Each PDF page may embed a full copy of the fonts used, even if only a few characters from each font appear. Font subsetting removes unused characters; full font embedding inflates file size unnecessarily.

Redundant metadata and thumbnails: PDF creation software sometimes embeds thumbnail previews, document history, and metadata that serve no purpose for the end recipient.

Uncompressed vector graphics: Complex charts, diagrams, and vector illustrations embedded without compression add to file size even though they contain no photographic data.

When to compress PDFs

• Email attachments: Most email providers limit attachments to 10–25 MB. A large contract or report that exceeds the limit needs compression before sending.
• Portal and form uploads: Government, bank, and university portals frequently cap uploaded file sizes at 2–5 MB. A scanned document exceeding this limit must be compressed.
• Cloud storage: Compressing PDFs before uploading to Google Drive, Dropbox, or OneDrive saves storage quota and speeds up sync.
• Mobile access: Sharing a PDF intended for viewing on a mobile phone should use a size optimised for mobile bandwidth.

The UtilsGo PDF Compressor processes your file entirely in your browser using client-side PDF manipulation libraries. Your documents are never transmitted to any server.