PDF Compressor
Compress PDF files in your browser - adjust DPI and JPG quality to reduce file size quickly and privately.
📄 Drag & Drop or Browse to upload PDF
Frequently Asked Questions - PDF Compressor
Answers to common questions about compressing PDFs, reducing PDF size.
How does this PDF compressor reduce file size?
This tool performs PDF compression by rasterizing pages and re-encoding them as JPEG at the chosen quality and DPI. You can adjust the quality and dpi as per the requirement and hit the Estimate Size button to check the possible estimated size.
Will compressing the PDF in the browser upload my file to a server?
No, Compression runs entirely in your browser. Whatever files you upload to compress the size, they are processed locally and do not gets uploaded to server at any time. So, your document remains private unless you choose to send it elsewhere.
Will compressed PDF keep selectable/searchable text?
No, because this tool rasterizes pages to images, text in the resulting PDF becomes part of an image and is no longer selectable, searchable, or copyable. If you need to preserve searchable text, consider server-side tools that optimize fonts and remove unused objects.
Which settings best reduce file size: DPI or Quality?
See, Both DPI and quality affect your file size. DPI decides how detailed the image is, if you lower it (around 96 - 150), the file becomes much smaller. Quality controls how much the image is compressed, lowering it (around 40 - 60) reduces size but can make the image look a bit rough. If your PDF is scanned, you can start with DPI 96 - 150 and quality 40 - 60 to reduce size a lot. But if your PDF has normal text, lowering DPI too much can make it less clear, so it’s better to reduce it slowly and check the result.
Why does estimated size sometimes differ from the downloaded file?
We offer two ways to check the file size. One is a quick estimate, and the other is an exact one. The quick estimate looks at 1-2 sample pages and gives you a rough idea. It’s fast, but it might not be fully accurate, especially if your PDF has different types of content. The exact estimate runs the full compression process and shows the final file size. This one is accurate and will match the file you download.
How long does client-side compression take?
The time it takes depends on things like how many pages your PDF has, the DPI you choose, and your device’s speed and memory. Small PDFs (1-5 pages) usually finish in just a few seconds. Bigger PDFs with many pages, especially at higher DPI, will take more time and use more memory.
Is there a page-count or file-size limit for client-side compression?
Browsers have limits when it comes to memory and performance. If your PDF is very large (lots of pages or heavy images), your browser might slow down or even run out of memory.
What types of PDFs compress best with image-based compression?
Scanned documents and PDFs with lots of images usually shrink the most, because the images inside them can be compressed. But PDFs that mostly have text or vector graphics don’t reduce much this way. In fact, converting them to images can make the text less clear and remove text selection.
Can I preview the compressed quality before compressing the entire file?
Yes, you can use the Estimate Size option. It runs the same compression process and shows you the result. Once it’s done, you can download the compressed version and check the quality.
Does compressing the PDF affect image quality for printing?
Yes, it can. If you lower the DPI or quality, the images may lose some detail. For good print quality, it’s better to use a higher DPI (around 300) and quality (80-100). If the PDF is only for screen viewing or sharing by email, you can use lower settings (DPI 96-150 and quality 30-60) to get a much smaller file size.
Is the compressed PDF compatible across PDF readers?
Yes, it is. The compressed file is a standard PDF with images inside, so it works with most modern PDF readers like Adobe Acrobat, browser viewers, Preview on macOS, and mobile PDF apps.
What if I need to keep text searchable and still reduce size?
If you want to keep the text selectable, don’t convert the PDF into images. Instead, use tools that optimize the file without changing the text. These tools reduce size by compressing data, removing extra elements, and optimizing fonts, while keeping the text clear and searchable.
Is my data safe - do you keep or log my files?
Yes, your data is safe. When you use the normal (browser-side) compression, your files stay on your device and are not uploaded anywhere. If you choose to use any server-side option (if available), you should check its privacy policy. But by default, everything runs in your browser, so you stay in full control of your files.