Compress PDFs & images
Reduce PDFs and images (JPEG, PNG, WebP) with quality presets or custom settings.
Quick start
- 1Choose one or more PDFs or images (JPEG, PNG, WebP).
- 2Pick a compression level.
- 3Click “Compress PDF”, “Compress image” or “Compress files” for multiple files. Then use the download link to save the finished result.
PDF compression levels
| Level | Technique | Text selectable |
|---|---|---|
| Lossless | Only the file structure is rewritten, images stay untouched | Yes |
| Light | JPEG images at 82 % quality, longest edge at most 4096 px | Yes |
| Balanced | JPEG images at 68 % quality, longest edge at most 1800 px | Yes |
| Strong | JPEG images at 50 % quality, longest edge at most 1200 px | Yes |
| Maximum | Every page is rebuilt at 110 dpi as a JPEG (55 % quality) | No |
| Custom | You set image quality (20–95 %) and longest image edge (600–4096 px) with two sliders | Yes |
“Light” to “Strong” and “Custom” re-encode embedded JPEG images of 24 KB or more and leave text and vector graphics untouched. An image is only replaced if that makes it at least 5 % smaller. “Maximum” renders every page as an image and builds a new PDF from them. This saves the most but costs text selection and searchability.
Compressing images
JPEG stays JPEG. PNG and WebP are saved as WebP where supported. If your browser cannot export WebP, PNG is used, or JPEG for opaque images if it is smaller. Transparency is preserved. Animated PNG/WebP files become a still image. The file extension always matches the actual format.
Images offer Light (82 %, 4096 px), Balanced (68 %, 1800 px), Strong (50 %, 1200 px) and Maximum (30 %, 800 px). Pixel limits apply to the longest edge; small images are never enlarged. Custom lets you set quality and edge length yourself.
A download appears when savings exceed 1 %. Images that are already well compressed may not get smaller. Use the before/after slider to compare quality. All files stay on your device.
Multiple files and ZIP downloads
Select multiple images and PDFs together. qPDF processes them one at a time to limit simultaneous memory use. “Download all as ZIP” appears when ready. The archive is prepared before you tap, so your tap starts a single download.
Every selected file is included in the ZIP. If savings do not exceed 1 %, the original is used. If a file cannot be processed, its error is shown and its original is included. The result list shows each file’s status and sizes. Duplicate filenames are numbered so no file overwrites another.
You can also download individual results or share them when supported by your device. If ZIP creation fails, individual files remain available and you can choose “Create ZIP again”. On iPhone and iPad, tap the downloaded ZIP in Files to extract it.
Understanding the result
Tips
- Start with “Balanced” and only go one level up if needed.
- Documents with lots of text and few images benefit little from compression.
- Scanned documents (images only) can be shrunk the most.