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You may need to increase brightness of PDF for a clearer, more readable display. In this post, MiniTool PDF Editor offers 4 approaches for PDF brightness increase. Select the methods that best fit your needs.

Why Do You Need to Increase PDF Brightness?

PDFs have become a popular shared digital document format. However, insufficient brightness can make PDFs difficult to read and cause eye strain after prolonged reading.

Therefore, adjusting PDF brightness is crucial. Increasing brightness makes text and graphics clearer and more prominent, significantly improving readability and the overall reading experience. For example:

  • PDFs scanned from inherently dark paper documents have poor contrast or contain shadows. Brightness increase makes text clear and easy to read without causing eye strain.
  • For those reading documents in low-light environments, higher brightness and contrast are essential for comfortable reading.
  • Adjusting contrast is crucial for some people with visual impairments, making documents easier to access.

In the following part, this guide will provide a step-by-step tutorial about PDF brightness increase.

How to Increase PDF Brightness?

To increase brightness of PDF, here are 4 approaches. You can pick one according to your needs.

Method 1. MiniTool PDF Editor

MiniTool PDF Editor, a desktop software, can help you adjust the brightness of PDF files. This powerful PDF editor allows you to adjust brightness by setting text color and page background color.

Moreover, this software is a feature-rich PDF Editor that can add/remove passwords, text, links, images, pages, backgrounds, and signatures to PDFs. It can also resize PDFs, merge PDFs, and translate PDFs.

Now, click the button below to download MiniTool PDF Editor. Then, run the download setup file and follow the prompted instructions to complete the installation.

MiniTool PDF EditorClick to Download100%Clean & Safe

Step 1. Right-click your PDF file and choose Open with > MiniTool PDF Editor.

Step 2. To adjust the PDF background color, click Edit > Background > Add Background, and then choose a bright background color. If there is background, choose Update Background. Then click OK.

MiniTool PDF Editor interface with the Add Background window, in which the Color section is emphasized.

Step 3. To increase the contrast between text and background, click Edit, Edit All, select text, and choose a dark color.

The Edit and Edit All options selected to adjust text color in MiniTool PDF Editor.

Method 2. Adobe Acrobat

Adobe Acrobat is primarily a tool for viewing, creating, and editing PDF documents. It also offers features to adjust the brightness of images in PDFs.

To do that with Adobe Acrobat, here are the steps:

  1. Open your PDF file with Adobe Acrobat.
  2. Right-click the image of the PDF, and then select Edit image.
  3. A new window will pop up. Click Adjust, and then drag the sliders for Contrast and Brightness.
  4. Finally, click Apply.
The Contrast and Brightness option selected to increase PDF brightness in Adobe Acrobat.

Method 3. Konfuzio PDF Tool

Konfuzio PDF Tool is a PDF brightness increase online tool. You can quickly increase PDF brightness using the brightness/contrast slider.

In addition, this PDF editor provides a range of basic tools for organizing, viewing, editing, signing, and converting files to PDF or other formats.

Tips:
Just note that you should avoid uploading sensitive documents due to privacy risks.

Now, follow the steps below to adjust PDF brightness:

  1. Go to the Konfuzio PDF Tool website on your web browser.
  2. Click Tools, and choose Adjust Colors/Contrast under Advanced.
  3. Select Click or Drag & Drop to upload your PDF file.
  4. Adjust the sliders for Contrast, Brightness, and Saturation as required.
  5. Click Download to save the file to your local storage.
The Contrast, Brightness, and Saturation option selected to increase PDF brightness in Konfuzio.

Method 4. i2PDF

The online tool i2pdf.com offers a dedicated Contrast PDF feature that improves the display and readability of scanned documents by allowing you to adjust the brightness and contrast.

Here is the guide:

  1. Open the i2PDF website (https://www.i2pdf.com/contrast-pdf).
  2. Click Choose Files to upload your PDF file.
  3. Once the file loads, adjust the Brightness and Contrast values (such as 1.5, 2.0, etc.).
  4. Then click Start.
  5. Once done, click Download to save the brightened PDF file.
The Contrast, Brightness, and Start button selected to increase the brightness of PDF in i2PDF.

How to increase brightness in a PDF file? This post presents four effective approaches, including online tools and desktop applications.Click to Tweet

PDF Brightness Increase FAQ

1. How to make PDF content darker?
To darken a PDF file, use an editor like MiniTool Partition Wizard to add a dark-colored background. To do that, go to Edit > Background> Add Background. Then select a dark color next to Color and click OK.
2. How to increase contrast on a PDF?
To increase PDF contrast, use built-in tools in Adobe Acrobat (Accessibility settings) or online tools, with auto-enhance features to set black/white points, ensuring better readability by boosting text/line clarity.
3. Can I brighten multiple PDFs at once?
Yes, you can brighten multiple PDFs at once, but it usually requires using professional PDF editors like Adobe Acrobat Pro to apply batch actions.
4. How to increase opacity in PDF?
To increase opacity in a PDF, use a PDF editor like Adobe Acrobat or other tools to select the specific text, image, or shape, find the Transparency/Opacity, and adjust the slider or alpha value to make it less transparent.
5. How to make a PDF file clear?
To make a PDF clear, either rescan the original at a higher DPI (300+) for scanned documents, adjust viewing settings in your PDF reader (like disabling font smoothing), or enhance contrast/brightness for blurry or low-quality scans.
6. Will increasing the brightness reduce the PDF file size?
No, simply increasing the brightness of a PDF file does not inherently or significantly reduce its file size.

Bottom Line

Adjusting the brightness of a PDF is a simple and effective method to make dimly lit and hard-to-read documents clear and readable. This post offers 4 effective methods for you. You can choose one according to your preference.

If you encounter issues when using MiniTool PDF Editor, contact us by sending an email to [email protected]. We’ll get back to you as soon as possible.

About The Author

Vega
Vega

Position: Columnist

Vega joined MiniTool as an editor after graduation. She enjoys helping people with computer problems, including disk management, data recovery, and more. She is constantly expanding her knowledge in related fields. And she will continue to bring more easy-to-understand professional articles to help people solve various problems on the PC. In her daily life, Vega enjoys hanging out with friends, shopping online, and listening to music. She is someone who knows how to enjoy life.