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Jun 19, 2025
How to Increase the DPI of a PDF (and What It Actually Means)
Say goodbye to disappointing PDFs and manual correction loops. The new Viesus Enhancer App for Enfocus Switchbrings fully automated AI-based image enhancement — including PDFs — directly into your print automation workflows.
Summary table
Concept | Description |
|---|---|
DPI in PDF | PDFs don’t have a DPI per se; DPI applies to images within the PDF. |
What Needs Enhancement | Only the embedded images, not vector text or element, require DPI adjustment. |
How to Increase DPI | Resample embedded images to higher resolution (more pixels per inch). |
Final Step | Replace low-res images in the PDF and re-export it. |
Tools Needed | AI upscaling tools like Viesus PDF Enhancer. |
What Does “DPI of a PDF” Really Mean?
When people ask how to increase the DPI of a PDF, they’re usually facing blurry prints or pixelated images in documents. The confusion lies in the fact that PDFs don’t have a DPI setting like raster images (e.g., JPEG or PNG) do. Instead, DPI applies only to:
Images embedded in the PDF
How those images are scaled when printed
The effective resolution based on image dimensions and print size
Example: If you embed a 1200x800 image and scale it to fill an A4 page (which is about 8.27 x 11.69 inches), the effective DPI becomes:
1200 pixels ÷ 8.27 inches ≈ 145 DPI
That’s below professional print quality, which usually starts at 300 DPI.
How to Actually Increase DPI in a PDF
Let’s break this down step-by-step:
Extract the Images from Your PDF
Use tools like:
Resample the Images to a Higher DPI
This step involves increasing the number of pixels—i.e., upsampling.
Options:
Use Viesus Cloud to automatically upscale the images to 300–600 DPI using AI.
Use manual tools like Photoshop (Image → Image Size → Resample with Bicubic Smoother).
⚠️ Note: Upsampling does not magically add detail—but with AI (like Viesus), you can recover sharpness and clarity better than with traditional interpolation.
Replace the Old Images in the PDF
Now that the images are higher resolution:
Reinsert them into your PDF using Adobe Acrobat, InDesign, or another PDF editor.
Ensure they are scaled correctly to maintain the new DPI.
Or do this fully automatic with Viesus
Re-export or Save the New PDF
Export the file with the enhanced images and ensure compression settings preserve image quality.
When Should You Increase the DPI?
You’re preparing a print-ready PDF and want to avoid pixelation
A client requests 300+ DPI for images
You’re fixing a scanned PDF with poor quality
When it’s unnecessary:
The document is mostly text
It will only be used digitally (e.g., on screen at 72–150 DPI)
Use Viesus for Automated AI Upscaling
Viesus streamlines this entire process:
Automatically scans your PDF
Detects low-resolution images
Replaces them with AI-enhanced, upsampled versions
Outputs a new PDF ready for professional use
🔁 All done in the cloud, no software installation required.
Final Thoughts
Increasing the DPI of a PDF isn’t about the file itself—it’s about improving the images inside it. By upsampling embedded images and re-exporting the document, you get crisper prints and higher quality output.
Whether you’re fixing marketing materials, photos, or scanned documents, Viesus gives you the fastest path to pixel-perfect PDFs.
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