OneDrive File Issues

How to Change OneDrive Mobile Scan DPI and Reduce PDF Size

Ayan Masood Oct 1, 2026 868 views

Question details

Users need to adjust the DPI or resolution in the OneDrive mobile scanner to reduce the final file size of scanned PDF documents.

How to Change OneDrive Mobile Scan DPI and Reduce PDF Size

Product: OneDrive Mobile App
Device & OS: not provided
Scenario: Scanning physical documents into PDF format using the OneDrive mobile application.
Observed behavior: The OneDrive scanner produces large PDF files and does not provide an option to manually configure or reduce the DPI setting.

Before you start

Ensure your OneDrive mobile app is updated to the latest version. While you cannot directly set a numerical DPI in the app, you can use built-in filters and distance techniques to optimize the file size.

Solution 1Recommended

Optimize Scan Distance and Apply Built-in Filters

Since OneDrive lacks a manual DPI setting, you can adjust your scanning distance and apply specific image filters to significantly reduce the final PDF size.

The size of your scanned PDF in OneDrive is largely dictated by the amount of color data and the capture resolution of your device's camera. By manipulating how the camera captures the document, you can lower the effective resolution.

Increase the scanning distance

Hold your mobile device slightly further away from the physical document. Making the document appear smaller on the phone screen will naturally reduce the capture resolution and the resulting file size.

Apply the Document filter

After capturing the image, tap the filter icon at the bottom of the screen and select the 'Document' filter. This optimizes the image for text and removes unnecessary background data.

Use the Black and White filter

If color is not essential for your document, switch to the 'Black and White' filter. This removes all color channels, which drastically reduces the overall file size of the PDF.

Optimize Scan Distance and Apply Built-in Filters

No Native DPI Control: The OneDrive document scanner does not offer manual DPI controls. Additionally, Microsoft Office Lens, which previously offered more scanning options, has been deprecated and is no longer supported.

Solution 2

Use Dedicated Scanner Software for DPI Control

If you require precise control over DPI, resolution, and compression levels, consider using a dedicated scanning application instead of the OneDrive app.

Use WPS Office to Scan and Compress PDFs Easily

WPS Office provides an all-in-one mobile app with a built-in document scanner and powerful PDF compression tools, allowing you to easily control your PDF file sizes.

1. Open Scanner: Launch the WPS Office mobile app and tap the '+' icon to access the built-in Scanner tool.
2. Capture and Filter: Capture your document and apply the B&W or Document filter to enhance text clarity and minimize file size.
3. Compress PDF: If the saved PDF is still too large, open it in WPS Office, navigate to 'Tools', and select 'PDF Compressor' to reduce the file size further.

Built-in document scanner that generates optimized PDF sizesPowerful PDF compression tool to easily shrink large scansFully compatible with Microsoft Office formats and standard PDFsFree and lightweight alternative for complete document management

microsoft office alternative - wps office

Frequently Asked Questions

Why are my OneDrive scanned PDFs so large?

The OneDrive mobile scanner automatically uses your camera's high resolution to ensure document clarity but lacks a manual DPI setting to lower this capture resolution, which often results in larger files exceeding 5MB.

Can I use Microsoft Office Lens to adjust DPI?

No, Microsoft Office Lens (Microsoft Lens) has been deprecated and is no longer officially supported. Users are encouraged to use the built-in OneDrive scanner or third-party alternatives.

How does the Black and White filter reduce PDF size?

The Black and White filter removes all color data from the scanned image. By storing only monochrome information, the file retains much less data per pixel, significantly shrinking the overall PDF size.

Document & File Issues