Improving Text Quality in PDFs: Techniques & Tools

Struggling with blurry or hard-to-read text in your PDFs? It’s a common issue, especially when dealing with scanned documents.

But don’t worry, there are simple ways to enhance PDF text quality and make your PDF text easier to read.

Below we show you the most common causes and possible solutions. We’ve also included a troubleshooting guide to help you find the best solution for your blurry PDF.

If you know your PDF already has selectable text, one quick solution is Smallpdf’s online PDF Editor. You can edit text, highlight key sections, or adjust formatting to make your PDF more readable in just a few clicks.

Or, if your text needs a deeper fix—like making text selectable or specific quality corrections—read on for practical techniques and tools that can help.

Let’s start with why.

Why Does My PDF Text Look Blurry?

Blurry or low-quality PDF text comes down to one of two issues:

1. Scanned Documents: When PDFs are created from scans, especially older or low-resolution scans, text clarity can suffer. This is especially true for handwritten text.

2. Low-Resolution PDFs: Documents saved at lower resolutions to reduce file size may compromise the sharpness of text and images.

If you’ve been wondering how to make text sharper in a PDF, the solution sometimes comes down to whether your PDF is a scanned image or a text-based file.

Now let’s find your solution.

Troubleshooting Blurry PDF Text: Quick Guide

Here’s a quick troubleshooting table to help assess your issue and possible solution:

Below we go step-by-step into these techniques to find what works for you.

Techniques to Enhance Text Quality in PDFs

1. Rescan the Original Source File

The easiest and fastest way to fix a blurry PDF image is to rescan the original document. Poor scans caused by a bump to the machine or a dirty scanner are hard to fix even with good PDF editing software.

When rescanning the original document, use higher resolution settings (300 DPI or higher is ideal). Choose grayscale or black-and-white mode for text-heavy documents for the clearest results.

If you need a fast, easy way to scan any document with high quality right from your phone. Smallpdf has a free PDF scanner app for iOS or Android phone.

If you don’t have access to the original source file to rescan, keep reading.

2. Use OCR to Convert Scanned PDFs

Scanned PDFs are basically image files. If your PDF text is blurry or unreadable because it’s part of a scanned image, Optical Character Recognition (OCR) is your best solution. OCR tools convert images of text into editable and searchable content.

Here’s what to do:

First, check if you can select the text in your PDF. Open your PDF and try highlighting the text (or press Cmd+A or Ctrl+A). If you copy the text, can you paste it into another doc?

• If you can select text: The issue might be font quality or poor contrast.
  • Solution: Skip OCR and jump below to try enhancing the text with tools like Smallpdf’s Editor or Mac Preview.
• If you can’t select text: The text is part of an image. Proceed with OCR.

Here’s how to make text readable in a PDF with OCR quickly:

1. Upload the scanned PDF to a tool like Smallpdf’s online OCR Converter.
2. Give it a second to read and convert the PDF image to editable text.
3. Export your PDF with readable text.

Next, you can copy-paste the text into a word processor to make manual adjustments like fixing missing characters or formatting errors. Or check the next step to edit or reformat the PDF directly.

3. Edit and Format Text to Make PDFs More Readable

For PDFs with editable text, try these simple formatting tweaks to enhance PDF readability:

• Add bold, italics, and underlines to improve text visibility and scannability.
• Highlight key sections with the highlighting tool to draw attention to important content.
• Increase font size to make tiny text easier to read.
• Use contrasting colors: Adjust text and background colors for better contrast.
• Remove unnecessary elements like watermarks or annotations that overlap text.

One of the easiest ways to do this is using Smallpdf’s online editing tools. Many editing features are free, and you don’t even need to sign up to try. If you need the most advanced tools, you can take advantage of the free trial to clean your PDF.

How to Sharpen Blurry PDF Text Using Mac Preview

If you’re a Mac user, there’s a simple method you can try to enhance PDF quality by adjusting contrast. This works best for PDFs where text is faint or hard to read, typical of scanned documents. It won’t fix severely blurry text, but it can improve readability for lighter or low-quality scans.

How to sharpen a PDF on Mac using Preview:

1. Open your PDF in Preview.
2. Go to ‘File’ > ‘Export.’
3. In the Quartz Filter dropdown, select ‘Lightness Decrease’
4. Choose a destination and click ‘Save.’

This technique can help to darken and sharpen faint text. For heavily blurred text, try OCR tools or rescan the original document for better results.

Frequently Asked Questions About Enhancing PDF Text Quality

How do you make text more readable in PDF? If you have access to the original document, try rescanning your document with higher resolution settings. The next step is to use OCR to convert scanned text to editable text. Then, adjust formatting like font size, bolding, or color contrast to improve readability.

How to enhance PDF text quality online? Use online tools like Smallpdf to run OCR and edit the text for clarity.

Why does my PDF text look blurry? Low-resolution scans or poor compression settings can make text appear blurry. Rescanning the document or using OCR can help improve clarity.

Can I enhance handwritten text in PDFs? OCR may not perfectly recognize all handwritten text, but rescanning at higher resolutions can improve your chances of better conversion. For very poor-quality handwriting, manual retyping might be necessary.

Final Thoughts: From Blurry to Brilliant

Improving text quality in PDFs can be a straightforward process when you use the right tools and techniques. Whether you’re rescuing a poorly scanned document or polishing up a digital file, Smallpdf’s suite of editing tools makes it easy to create PDFs that look professional and are easy to read.

Give it a try today—your eyes (and readers) will thank you.