PDF Compressor
Adobe and Smallpdf want the file on their server. This page compresses in the tab.
Adobe and Smallpdf want the file on their server. This page compresses in the tab. If the PDF can’t leave the machine, that’s the whole reason to use it, not a slogan.
Drop the file. Pick a size you can actually email. Open the result before you send it. Compression that you didn’t check is how a scan becomes unreadable.
How to use it
- Images are the weight. A 40MB slide deck is photos, not text. Downsampling those is the win. Re-saving text pages barely moves the needle.
- Pick a target you can defend. “Email” is ~10MB on a lot of gates. “Print” should not be the email preset.
- Encrypted or permission-locked PDFs won’t compress until you unlock them. That’s the PDF, not the tool.
- Run it twice if you want. The second pass rarely pays. If it’s still huge, the file is scans at 600dpi and you need a lower dpi, not another click.
When it breaks
- Already-flattened scans look the same and shrink a lot, or look like mud and shrink a lot. Check page 3, not page 1.
- Form fields, some links, and bookmarks can vanish depending on the rewrite. If the form has to keep working, don’t flatten it for size.
- This is not OCR. A compressed scan is still not searchable text.
Select a PDF to compress
Features
- The PDF never leaves this device: no Adobe, Smallpdf, or iLovePDF upload
- Downsample embedded images at low / medium / high settings
- Before/after byte counts so you can see if the file was already compressed
- Text stays selectable; we are not rasterizing pages into a scan
Common Use Cases
- Shrink a scanned contract that Gmail rejects at 25 MB, without an upload queue
- Compress a deck that contains huge PNG exports
- Avoid dropping a confidential PDF on a third-party compressor
- See that a text-only PDF barely shrinks (images are the lever)
Adobe and Smallpdf want the file on their server
Adobe and Smallpdf want the file on their server. This page compresses in the tab. If the PDF can’t leave the machine, that’s the whole reason to use it, not a slogan.
Drop the file. Pick a size you can actually email. Open the result before you send it. Compression that you didn’t check is how a scan becomes unreadable.
Images are the weight. A 40MB slide deck is photos, not text. Downsampling those is the win. Re-saving text pages barely moves the needle. Pick a target you can defend. “Email” is ~10MB on a lot of gates. “Print” should not be the email preset. Encrypted or permission-locked PDFs won’t compress until you unlock them. That’s the PDF, not the tool.
Run it twice if you want. The second pass rarely pays. If it’s still huge, the file is scans at 600dpi and you need a lower dpi, not another click.
Examples
Original: ~25 MB, 300 DPI page images
Medium downsample → often well under 10 MB
Text layer remains searchableOriginal: 180 KB of vector text
High compression → still ~150-180 KB
Do not expect a 10x winoriginal.pdf → compress high → compress high again
Second pass hurts photos, barely saves bytesFrequently Asked Questions
Adobe and Smallpdf want the file on their server. This page compresses in the tab. If the PDF can’t leave the machine, that’s the whole reason to use it, not a slogan.
Images are the weight. A 40MB slide deck is photos, not text. Downsampling those is the win. Re-saving text pages barely moves the needle. Pick a target you can defend. “Email” is ~10MB on a lot of gates. “Print” should not be the email preset.
Encrypted or permission-locked PDFs won’t compress until you unlock them. That’s the PDF, not the tool. Run it twice if you want. The second pass rarely pays. If it’s still huge, the file is scans at 600dpi and you need a lower dpi, not another click.
Already-flattened scans look the same and shrink a lot, or look like mud and shrink a lot. Check page 3, not page 1. Form fields, some links, and bookmarks can vanish depending on the rewrite. If the form has to keep working, don’t flatten it for size. This is not OCR. A compressed scan is still not searchable text.
Common Mistakes
Tips
- Keep the uncompressed original. Email the compressed copy.
- Start at medium. High is for attachment caps, not archival.
- If the tab freezes, the file is too large for in-memory pdf-lib; split first.