Compress PDF
Reduce PDF file size in the browser.
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About Compress PDF
Big PDFs are usually big because of photos: scans and image-heavy exports carry JPEGs far larger than a screen needs. The tool looks through the file for embedded JPEG images of 20 KB or more, redraws each one in your browser at lower quality, scales down any whose longer side passes 2000 pixels, and rewrites the document with packed object streams. Text-only files may barely change, and the result panel shows the before and after sizes.
Features
- Re-encodes embedded JPEG images at a lower quality
- Scales down images whose longer side is over 2000 pixels
- Skips CMYK JPEGs and images under 20 KB rather than risk damaging them
- Hands back your original file if the result would not be smaller
- Shows original size, new size and the number of images recompressed
Limitations
- Only plain JPEG images are recompressed. Text, vector graphics and images stored in other ways are not touched, so a text-heavy PDF may shrink little or not at all.
- Recompression is lossy and you cannot choose the quality, so photographs can look softer afterwards.
- Each file can be up to 50 MB, and saving the compressed copy needs a free account.
How it works
- Drop in the PDF; its file size is shown under the name.
- Select Compress PDF and wait while the images are processed.
- Read the result panel: original size, compressed size, the reduction and how many images were recompressed.
- Select Download to save the file, which keeps your original name with _compressed added.
Frequently asked questions
- It depends on what is inside, and the tool does not predict it. A scan made of large JPEGs can shrink noticeably, while a mostly-text PDF has little to recompress. The result panel shows the exact before and after sizes so you can judge.
- You get your original file back. The tool compares the new version with the original and only keeps it when it is smaller; otherwise it says it could not shrink the file and returns the original unchanged.
- Only images stored as a single plain JPEG filter are recompressed. Scans saved as fax-style CCITT, JBIG2 or JPEG 2000 images, or as raw bitmaps, are skipped on purpose, as are very small images and CMYK photos.
- No, text and vector graphics are not turned into images, so they stay sharp. Only the embedded JPEG photos are re-encoded, and nothing leaves your browser during that work. Saving the result is the step that asks for an account.