Tools / PDF Comment Markup

PDF Comment Markup

Add comments and markup to your PDF with our free online tool. Upload a PDF, highlight text or add notes, and download the result in just a few clicks.

🖼️ Scaling millions of product images? 💡Automate, optimize, and deliver faster. 👉 Talk to a Media Expert

PDF Comment Markup

Or drag your PDF here

PDF files only · Max 20MB

★★★★★
4.7 (22 reviews)

Looking to mark up PDFs in bulk?

Sign up to use our API in your next project and automate PDF markup at scale.

Free Online PDF Comment Markup Tool

Add comments and markup to your PDF in seconds, right in your browser. No downloads needed, no watermarks, no sign-up.

Why use our PDF Comment Markup tool?

Highlight text and add comments and markup to any PDF right in the browser, with no downloads or ads. Developers can also use our API to mark up PDFs automatically across their workflows.

Built for the browser

Work right in your browser, free, with no software to install and no watermarks.

Quality preserved

Cloudinary keeps your PDF crisp and true to the original, end to end.

Performance Optimization

Your thumbnail image is delivered in the best format and quality for every device, browser, and connection, automatically.

Mark up PDFs in bulk

Process one PDF or thousands. Use our free API to add comments and markup automatically across your projects.

Workflow Automation

Set up presets to mark up PDFs automatically on upload, ready for delivery in seconds.

Format versatility

Works with all major formats, so your thumbnail image looks sharp anywhere you share it.

How to mark up a PDF in 3 steps

Get your marked-up PDF in 3 simple steps. Upload your PDF, add your markup, and download the result in seconds.

Upload your PDF

Drag and drop your PDF into the browser, or upload it from your device in seconds.

Add your markup

Highlight text or add comments in the color you choose, and preview the changes on your PDF.

Download your PDF

Once it’s ready, download your marked-up PDF, with no watermarks, ready to share or publish.

Go beyond basic markup

A woman and a golden retriever in the mountains. They're sitting, facing away from the camera while the dog noses the woman. They're surrounded by natural splendor including majestic mountains, puffy clouds, and evergreen-studded hills.
An un-cropped image overlaid with a cropping window showing how it would be cropped by Cloudinary.
An arrow pointing from the original asset to the cropped asset
A woman and a golden retriever in the mountains. They're sitting, facing away from the camera while the dog noses the woman. They're surrounded by natural splendor including majestic mountains, puffy clouds, and evergreen-studded hills.
The same asset cropped using the following settings: Aspect Ratio: 1:2. Crop Mode: Content-Aware.
Images
Videos
Crop Mode
Aspect Ratio
Original
18 MB

We’re showing a resized version of the original asset to avoid slow loading speeds. View the original.

The original asset:
JPEG
135 KB
WebP
135 KB
AVIF
90 KB
JPEG XL
94 KB
The image after being optimized using the following settings: Quality: Auto. Width: 1000px.
Original
18 MB

We’re showing a resized version of the original asset to avoid slow loading speeds. View the original.

The original asset:
JPEG
135 KB
WebP
135 KB
AVIF
90 KB
JPEG XL
94 KB
The image after being optimized using the following settings: Quality: Auto. Width: 1000px.
Images
Videos
Quality
Width
An un-cropped image overlaid with a croppingai window showing how it would be cropped by Cloudinary.
An arrow pointing from the original asset to the cropped asset
The same asset cropped using the following settings: Aspect Ratio: 1:1. Crop Mode: Content-Aware.
Images
Videos
Crop Mode
Aspect Ratio
The original image:
An arrow pointing from the original asset to the transformed asset.
The personalized image:
The original image:
The personalized image:
Product Photos
Backgrounds
Overlays
Duration
Full length video: Surfing Trip
An arrow pointing from the original video to the AI-generated preview.
Duration
A shorter video preview generated by Cloudinary's AI using the following settings: Duration: 15 seconds. Max Clips: 9. Min Clip Length: 1 second.
Videos
Duration
Max Clips
Min Clip Length
URL:
/ar_0.5,c_fill,g_auto,w_433/q_auto/f_auto/hiking_dog_mountain.jpg
cloudinary.image("hiking_dog_mountain.jpg", {transformation: [
  {aspect_ratio: "0.5", gravity: "auto", width: 433, crop: "fill"},
  {quality: "auto"},
  {fetch_format: "auto"}
  ]})
new CloudinaryImage("hiking_dog_mountain.jpg")
  .resize(
    fill()
      .width(433)
      .aspectRatio(0.5)
      .gravity(autoGravity())
  )
  .delivery(quality(auto()))
  .delivery(format(auto()));
new CloudinaryImage("hiking_dog_mountain.jpg")
  .resize(
    fill()
      .width(433)
      .aspectRatio(0.5)
      .gravity(autoGravity())
  )
  .delivery(quality(auto()))
  .delivery(format(auto()));
new CloudinaryImage("hiking_dog_mountain.jpg")
  .resize(
    fill()
      .width(433)
      .aspectRatio(0.5)
      .gravity(autoGravity())
  )
  .delivery(quality(auto()))
  .delivery(format(auto()));
new CloudinaryImage("hiking_dog_mountain.jpg")
  .resize(
    fill()
      .width(433)
      .aspectRatio(0.5)
      .gravity(autoGravity())
  )
  .delivery(quality(auto()))
  .delivery(format(auto()));
CloudinaryImage("hiking_dog_mountain.jpg").image(transformation=[
  {'aspect_ratio': "0.5", 'gravity': "auto", 'width': 433, 'crop': "fill"},
  {'quality': "auto"},
  {'fetch_format': "auto"}
  ])
(new ImageTag('hiking_dog_mountain.jpg'))
	->resize(Resize::fill()->width(433)
->aspectRatio(0.5)
	->gravity(
	Gravity::autoGravity())
	)
	->delivery(Delivery::quality(
	Quality::auto()))
	->delivery(Delivery::format(
	Format::auto()));
cloudinary.url().transformation(new Transformation()
  .aspectRatio("0.5").gravity("auto").width(433).crop("fill").chain()
  .quality("auto").chain()
  .fetchFormat("auto")).imageTag("hiking_dog_mountain.jpg");
cl_image_tag("hiking_dog_mountain.jpg", transformation: [
  {aspect_ratio: "0.5", gravity: "auto", width: 433, crop: "fill"},
  {quality: "auto"},
  {fetch_format: "auto"}
  ])
cloudinary.Api.UrlImgUp.Transform(new Transformation()
  .AspectRatio("0.5").Gravity("auto").Width(433).Crop("fill").Chain()
  .Quality("auto").Chain()
  .FetchFormat("auto")).BuildImageTag("hiking_dog_mountain.jpg")
cloudinary.image('hiking_dog_mountain.jpg').transformation(Transformation()
	.resize(Resize.fill().width(433)
.aspectRatio(0.5)
	.gravity(
	Gravity.autoGravity())
	)
	.delivery(Delivery.quality(
	Quality.auto()))
	.delivery(Delivery.format(
	Format.auto())));
imageView.cldSetImage(cloudinary.createUrl().setTransformation(CLDTransformation()
  .setAspectRatio("0.5").setGravity("auto").setWidth(433).setCrop("fill").chain()
  .setQuality("auto").chain()
  .setFetchFormat("auto")).generate("hiking_dog_mountain.jpg")!, cloudinary: cloudinary)
MediaManager.get().url().transformation(new Transformation()
  .aspectRatio("0.5").gravity("auto").width(433).crop("fill").chain()
  .quality("auto").chain()
  .fetchFormat("auto")).generate("hiking_dog_mountain.jpg");
cloudinary.image('hiking_dog_mountain.jpg').transformation(Transformation()
	.resize(Resize.fill().width(433)
.aspectRatio(0.5)
	.gravity(
	Gravity.autoGravity())
	)
	.delivery(Delivery.quality(
	Quality.auto()))
	.delivery(Delivery.format(
	Format.auto())));
cloudinary.image {
	publicId("hiking_dog_mountain.jpg")
	 resize(Resize.fill() { width(433)
 aspectRatio(0.5F)
	 gravity(
	Gravity.autoGravity())
	 })
	 delivery(Delivery.quality(
	Quality.auto()))
	 delivery(Delivery.format(
	Format.auto())) 
}.generate()
new CloudinaryImage("hiking_dog_mountain.jpg")
  .resize(
    fill()
      .width(433)
      .aspectRatio(0.5)
      .gravity(autoGravity())
  )
  .delivery(quality(auto()))
  .delivery(format(auto()));

Frequently Asked Questions

It lets you highlight text and add comments and markup to a PDF, quickly and easily, right in your browser.

Upload your PDF and add highlights or comments in your browser. The tool applies them and gives you the marked-up PDF, ready to download.

Yes, it’s free to use online. Just upload your PDF, add your markup, and download the result.

Yes. Developers can use Cloudinary’s API to add comments and markup and automate it across their workflows at scale.

Highlights and comments in the color of your choice, so you can review, annotate, and share PDFs without extra software. You might also like our PDF Stamp Annotations, or browse all our free tools.

Get Free API Get Free API