How to compress PDF files
Add one or more PDFs, choose Compression preset or Custom settings, then click Compress. The page renders each page as a JPEG and places those images in a new PDF. The selected file data stays in the browser; the script does not send it to a server.
- Drop PDF files here, or click browse files.
- Choose Compression preset, or select Custom and set Resolution and Quality.
- Turn on Target file size to test each file against a requested size, then enter Target size (per file) in KB or MB.
- Click Compress and wait for each readable file to reach Complete.
- Select Preview or Download for one output, or use Download all as ZIP for the completed outputs.
Click Remove beside a file to take it out of the current list before compression. The remaining readable files are processed sequentially.
How to reduce PDF file size with the presets
Compression preset sets the resolution and JPEG quality used to rebuild every page:
- Screen (96 DPI) uses
55%quality. - eBook (150 DPI) uses
70%quality. - Print (300 DPI) uses
82%quality. - Custom lets you set Resolution from
72to300 DPIand Quality from10%to95%.
Moving either Custom slider selects Custom. Higher resolution and quality can produce a larger output, and the source pages also affect the final size.
Compression preset: eBook (150 DPI)
Quality: 70%
report.pdf -> report-compressed.pdfHow target PDF file size works
Turn on Target file size to reveal Target size (per file). Enter a positive number and choose KB or MB. Blank, zero, and negative values show Enter a positive number for the target file size, and compression waits for a valid value.
Target mode rebuilds the whole PDF at different JPEG quality levels. It makes up to five checks between quality 10 and the selected quality. If none meets the target, the tool rebuilds the PDF at quality 10. The final file can still be larger than the requested size.
What the estimate and compressed PDF show
After a PDF loads or a setting changes, the table shows an estimated output size. The estimate renders page 1, applies the current quality, and uses the page count to estimate the full document. Output Size appears after all pages have been rebuilt.
After compression, Preview opens page 1 in Before (original page) and After (compressed page). A file named report.pdf downloads as report-compressed.pdf. Download all as ZIP includes the completed outputs.
Each output page is a JPEG image inside a new PDF. Text in that output is not selectable or searchable, and PDF data outside the rendered page is not carried over. Keep the original PDF when that data is needed.
The file picker accepts files identified as PDFs or files with a .pdf name. An unreadable file is marked Excluded: PDF could not be read. A compression failure appears as an Error row, while readable files stay in the list with their individual statuses.
Where compressing a PDF comes up
For a scanned report, choose Screen or eBook, check the estimate, and inspect the first page before downloading the rebuilt copy.
For several PDF attachments, add them together. Compress processes the readable files one at a time, and Download all as ZIP collects the completed outputs.
Use Print for a handout when you want the 300 DPI preset. Use eBook or Screen for on-screen reading.
When to use PDF Compress Tools
Use this page when you want a rebuilt PDF with adjustable image resolution, JPEG quality, or a per-file size target. PDF Compress Tools is the parent category for the available PDF size-reduction tools.
Frequently asked questions
How do I compress PDF files in my browser?
Add the PDFs, choose Compression preset or Custom settings, click Compress, and download the completed outputs. The page processes the selected file data in the browser.
Will a compressed PDF keep selectable text?
No. Each page becomes a JPEG image in the rebuilt PDF, so text is not selectable or searchable in the output.
Can I reduce a PDF to a target file size?
Target file size mode tests several JPEG quality levels against the requested per-file size. It can make up to five attempts, but the final output may still exceed the target.
Can I compress several PDF files at once?
Yes. Add multiple PDFs, then use Compress to process the readable files sequentially. Download all as ZIP collects the completed outputs.