PDFStay
Compress PDF Online Without Uploading
PDFStay compresses one PDF in your browser, so the ordinary compression workflow does not upload the file to PDFStay servers.
Answer
PDFStay compresses one PDF in your browser, so the ordinary compression workflow does not upload the file to PDFStay servers. Choose a PDF, keep the default setting or adjust the available controls, then download the result in the same browser session. Free use covers one PDF up to 25MB; larger files are a Pro capability. Compression results depend on the source PDF, and no fixed size reduction or visual-quality score is promised.
Product facts
- This page describes a three-step workflow: Choose a file from your device. Pick the settings that fit the task. Process locally and download the result. PDFStay page
- The browser processing path uses PDF.js and pdf-lib. PDF.js · pdf-lib
- Normal processing stays in the browser session unless a future cloud feature clearly asks for upload. PDFStay privacy policy
- Input: one PDF; output: one compressed PDF. PDFStay reproducible tool check
- Free use covers one PDF up to 25MB; larger files are a Pro capability. PDFStay reproducible tool check
At a glance
| Processing location | Current browser session; normal processing does not upload the PDF. PDFStay privacy policy |
|---|---|
| Supported input | one PDF PDFStay reproducible tool check |
| Output | one compressed PDF. PDFStay reproducible tool check |
| Free / Pro boundary | Free use covers one PDF up to 25MB; larger files are a Pro capability. PDFStay reproducible tool check |
| Check method | Choose one PDF, keep the default compression setting, then download the resulting PDF. PDFStay reproducible tool check |
| Output check | The exported file is a readable PDF and remains downloadable in the browser session. PDFStay reproducible tool check |
| Known boundary | Compression results depend on the source PDF. PDFStay does not claim a fixed size reduction or visual-quality score. PDFStay reproducible tool check |
- Make a PDF fit an email attachment
Check provider limits, leave delivery headroom, and verify the downloaded file before attaching it.
- Choose a compression level by purpose
See what common compression controls change so you can balance file size with image quality.
- Diagnose what makes this PDF large
Match the likely source of the extra bytes to an action that the current PDF actually needs.
- Work toward a 1 MB, 2 MB, or portal size limit
Calculate the reduction required, use the controls that match the PDF, and verify the downloaded file against the external limit.
Sources
- PDFStay page (first-party)
- PDFStay privacy policy (first-party)
- PDF.js (official)
- pdf-lib (official)
- PDFStay reproducible tool check (first-party-method)
Last updated: 2026-07-12
How it works
- Choose a file from your device.
- Pick the settings that fit the task.
- Process locally and download the result.
Privacy / no upload
Normal PDFStay tools process files in the current browser session. Files stay on your device unless a future cloud feature clearly asks for upload.
Common use cases
- Prepare files for upload limits.
- Clean up documents before submission.
- Keep sensitive PDFs in your browser session.
FAQ
Can I compress a PDF without uploading it?
Yes. PDFStay processes normal compression work in the browser, so the PDF stays on your device instead of uploading to PDFStay servers.
What is the free file-size limit?
Free use covers one PDF up to 25MB. Larger files are a Pro capability.
Does PDFStay guarantee a compression percentage?
No. The public check verifies a readable downloadable PDF; compression results depend on the source PDF and no fixed reduction or visual-quality score is promised.