Compress PDF
Shrink a PDF by re-encoding and downsampling its images and stripping metadata. Every number you see afterwards is measured from the actual output file — this tool shows the bytes, and if the output would come out bigger, it keeps your original and says so.
Select a PDF file or drop it here
Compression level
Light
Visually near-identical. Images re-encoded at quality 85 only when that makes them smaller; no downscaling.
Recommended
Images downsampled to 150 DPI and re-encoded at quality 75. Typical scanned PDFs shrink a lot.
Strong
Images downsampled to 96 DPI and re-encoded at quality 55. Visible softening on zoom is possible.
What each level actually does
- Light — document info/metadata stripped (if enabled), unreachable objects dropped, file re-serialized; images re-encoded at JPEG quality 85 with no resizing, and kept only when the re-encode is smaller.
- Recommended — everything Light does, plus images larger than 150 DPI for their on-page size are downsampled to 150 DPI and re-encoded at JPEG quality 75.
- Strong — everything Recommended does, at a 96 DPI cap and JPEG quality 55.
- In every level: embedded fonts are carried through untouched, and images the browser cannot decode (JPEG 2000, JBIG2, CCITT fax, indexed/CMYK, or images with transparency masks) pass through unchanged.
Advanced
150 DPI
75 / 100
"Lossless" here has a precise meaning: structural re-serialization and metadata removal only. No image is re-encoded, so nothing you can see changes. In the other modes images ARE re-encoded — that is lossy by definition, though usually hard to spot at these settings.