Compress a PDF online
Shrink a PDF by recompressing its JPEG images, without rasterizing the pages: the text stays selectable. Directly in your browser.
or click to select it
Shrink a PDF by recompressing the JPEG images it contains, without rasterizing the pages: the text stays real, selectable text. Directly in your browser.
Finds the JPEG images embedded in the PDF and recompresses them at a lower quality (and, in the 'small file' profile, a lower resolution), leaving the text, vector graphics and the rest of the document structure untouched. If a particular image can't be safely recompressed, it's left as is.
Use cases
- Shrink a photo-heavy PDF so it fits in an email.
- Meet a form's or platform's upload size limit.
- Save cloud or device storage space.
How it works
- 1
Upload your PDF
Drag the file or pick it from your device.
- 2
Choose a quality profile
High quality, balanced or small file.
- 3
Download the result
With the original and final size visible for comparison.
Technical details
Walks the PDF's low-level object graph with @cantoo/pdf-lib looking for image streams filtered with DCTDecode (JPEG), decodes them with the browser's native decoder, and re-encodes them via canvas at a lower quality. It only touches images in direct RGB color: ones using CMYK, grayscale, an indexed palette or an ICC color profile are left unmodified to avoid risking altered color, so the exact reduction depends on how many RGB images your PDF has.
Frequently asked questions
Why did my PDF barely shrink?
It may already be optimized, have few JPEG images, or its images may use a color space (CMYK, grayscale, ICC profile) this tool deliberately doesn't recompress to avoid altering color.
Does it lose text or vector graphics quality?
No. Only the JPEG images are recompressed; the PDF's text and vector graphics are untouched and keep their original quality and sharpness.