Compress PDFs with the available controls
Add readable PDF files and choose the settings you need. The tool rebuilds usable files automatically. The tool processes multiple files sequentially.
- Drop one or more PDF files onto the drop zone, or click browse files.
- Choose a preset, adjust the Custom controls, or enable Target file size.
- Review the estimate and compression progress as the current settings are applied automatically.
- After a file is compressed, use its Preview or Download action. Use Download all as ZIP for the available outputs.
Use Remove to delete a file from the current list before compression.
Choose a compression preset or custom settings
Under Compression preset, choose the setting that matches your intended level of detail:
- Screen:
96 DPIand55% quality. - eBook:
150 DPIand70% quality. - Print:
300 DPIand82% quality. - Custom: set Resolution from
72to300 DPIand Quality from10%to95%.
Changing either Custom slider selects Custom. The file size and visual result depend on the source PDF and the settings you choose.
Use target file size mode carefully
Enable the Target file size checkbox to show the Target size (per file) field. Enter a positive number and choose KB or MB. An invalid value shows Enter a positive number for the target file size.
During compression, the tool rebuilds the entire PDF at different JPEG quality levels, starting at the currently selected quality. It makes a bounded search of up to five attempts and can fall back to quality 10. This is a best-effort process: the final output may still be larger than the requested target.
Read estimates and use the preview
After files load or settings change, the tool calculates an approximate estimate. It renders only page 1, extrapolates from the PDF's page count, and displays the result for guidance. The final output size is calculated only after every page has been rebuilt.
The preview shows page 1 of the selected file in the Before (original page) and After (compressed page) tabs. Preview and download actions appear only after compression. The preview note shows the current DPI and quality controls; in target-size mode, those values may not be the quality used internally by the search.
Understand the rebuilt PDF's limitations
Each page is rendered, converted to a JPEG image, and placed into a new PDF. The output preserves the rendered page appearance rather than the original PDF structure. Text is not selectable or searchable, and non-visual PDF features are not preserved.
Keep a copy of the original when you need selectable text or other original features. The Print preset may keep pages closer to the original visually, but it does not preserve selectable text.
Handle excluded files and compression errors
- Non-PDF files are filtered out when files are added.
- An unreadable PDF is marked Excluded: PDF could not be read.
- If estimation cannot read the PDFs, the tool shows Estimates are unavailable for these PDFs.
- A failed compression appears as an Error row.
Files are processed sequentially. The implementation does not define a hard file-count, file-size, page-count, or memory limit, and it does not guarantee behavior for very large or complex PDFs.
Frequently asked questions
Does compressing a PDF upload my file anywhere?
No. Every page is rendered, re-encoded and reassembled into a new PDF entirely inside your browser. Your file never leaves your device.
Will the text still be selectable after compressing?
No. This tool compresses by re-rendering each page as an optimized image, which is how most of the file-size savings come from. That means text is no longer selectable or searchable in the output. If you need to keep selectable text, only compress a copy, or use a lighter Print preset which keeps pages closer to the original.
How does target file size mode work?
The tool rebuilds the entire PDF at several JPEG quality levels during a bounded search of up to five attempts. It starts at the currently selected quality and can fall back to quality 10. The requested size is not guaranteed, so the final file may still exceed the target.