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PDF Compressor

Reduce PDF file size with lossless stream recompression while preserving embedded image quality.

Choose one readable PDF and run lossless stream recompression. Compare the original and output byte counts; keep the original if the optimized copy is not smaller.

This is lossless structural optimization. Embedded photographs are not recompressed, so image-heavy PDFs may not get smaller.

Your PDF stays on this device. The processing engine loads only after you start.

How to use

Reduce structural PDF overhead without changing photos

Reduce PDF file size with lossless stream recompression while preserving embedded image quality.

Step by step

  1. Provide the source using: Optimize PDF structure without changing image quality.
  2. Choose: Compress PDF. Inspect the result before copying, downloading or using it elsewhere.
  3. Choose one readable PDF and run lossless stream recompression. Compare the original and output byte counts; keep the original if the optimized copy is not smaller.

Choosing the settings

OptionWhat changes
Compress PDFThe optimizer recompresses PDF data streams and packs document objects using lossless settings. It does not rasterize pages, re-encode embedded photos or guarantee a smaller file. If the optimized result is not smaller, no replacement download is offered.
Optimize PDF structure without changing image qualityUse a readable PDF up to 50 MB and 300 pages. Encrypted or damaged files may not be supported by the selected operation. Processing runs locally in a dedicated worker; closing the page or cancelling stops the job.

Example and expected result

Decision example, not a measured saving: if a 5,000,000-byte PDF recompresses to 5,100,000 bytes, it is larger. Keep the original; this optimizer offers a replacement download only when the result is smaller. Embedded photographs are not re-encoded.

If it is not working

  • Use a readable PDF up to 50 MB and 300 pages. Encrypted or damaged files may not be supported by the selected operation. Processing runs locally in a dedicated worker; closing the page or cancelling stops the job.
  • If a PDF fails, reopen the original in a PDF viewer first. Use an unlocked copy for operations that reject encryption, and a flattened copy where forms are unsupported. Cancel a stalled job and try a smaller document; keep the original.

What this PDF optimizer changes

The optimizer recompresses PDF data streams and packs document objects using lossless settings. It does not rasterize pages, re-encode embedded photos or guarantee a smaller file. If the optimized result is not smaller, no replacement download is offered.

File and device limits

Use a readable PDF up to 50 MB and 300 pages. Encrypted or damaged files may not be supported by the selected operation. Processing runs locally in a dedicated worker; closing the page or cancelling stops the job.

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