Reduce PDF size while keeping the document readable
Large photos and scanned pages often account for most PDF size. Compression reprocesses those images, so the reduction varies by document. A text-only or already optimised PDF may shrink very little or become larger. Choose quality for the intended use, rather than judging the result by file size alone.
Step by step
- Keep an original copy and upload the PDF.
- Try 150 DPI for screen reading and email. Choose 300 DPI for fine print or printing; 72 DPI can lose more detail.
- Download the result, compare its size and zoom into a page containing small text.
Example scenario
Example: a photo-heavy application exceeds an upload limit. Try 150 DPI first, then inspect a 72 DPI version if necessary. If identification numbers or barcodes become unclear, return to higher quality. This tool does not guarantee a particular MB target.
Check your result
Check page count, drawings and links after conversion. Reprocessing can invalidate digital signatures, so retain the signed original. If the output is larger, use the original copy. Unlock encrypted files only when you have permission to do so.
Frequently asked questions
Is compression always lossless?
No. Image reprocessing can lose detail. Inspect the output before replacing the original.
Is lower DPI always better?
No. Small text, drawings and printed documents may require higher resolution. Choose the smallest version that remains readable.
Keep an original copy before processing your file. Examples are illustrative; results depend on your document.