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PDF annotation: 11 features for high-quality markups

8 min read
Katie Oberthaler

If you’ve ever tried to annotate PDF files, you know it’s not as straightforward as reviewing and commenting on other digital file formats. Being able to easily mark up a pdf for design, text updates is crucial 

Yet, the Portable Document File (PDF) remains a common file type among creative and marketing teams. Naturally, reviewers want to correct typos, suggest color enhancements, and leave comments in the PDFs. PDF annotation tools have evolved to do just that. 

Remote marketing teams can't gather around a PDF at the office and provide feedback. They need a way to share instant feedback that doesn't require using email, Slack, or some other digital channel where feedback languishes. Plus, feedback can be unclear, if you aren’t able to comment on a specific area within a creative asset. 

PDF proofing and annotation often require a detailed level of markup and comparison, plus lots of commenting that you can't achieve in other digital channels.

In this guide, we'll explore the primary use cases for PDF annotation tools and the most current features to consider when using PDF annotation software.

What we'll cover


Top use cases for PDF annotations

PDF mark ups are beneficial for a variety of reasons. Let’s take a look at some of the scenarios where they would prove helpful.

Preventing changes directly on a PDF file

Whether you’re writing a novel, a contract or advertising copy, you may need someone to review your content before you publish it. You may also prefer to see changes as suggestions, instead of giving someone access to the words and design elements.  

By saving your work as a PDF document, you know other people can read but can’t edit the content itself. Instead, they can add sticky notes with their suggested changes and highlight sections that need clarification.


Making notes

PDF annotations often occur in complex and lengthy documents, such as technical specifications or manuals 

For example, as you read through the document, you can add notes about anything significant or questions that come to mind. 

You could also add notes to track what you have or haven’t implemented from the instructions.

Artwork and design feedback

You can add PDF annotations when you’re reviewing and approving creative assets. For example, you might want to ask the designer to change the look of the CTA: “I can hardly see the CTA – could you make it more visible?” Or change the background color: “Could you make the sky darker blue?”

PDF Markups in Ziflow app - Trip to Switzerland photo being reviewed and commented on

Ad proofing

PDF annotations are indispensable when your marketing, creative, and design teams are collaborating on your latest ads. You can review side-by-side comparisons of the copy and images for print and digital ads. That means you can work faster and produce ads with fewer errors, versions, and revisions.

Ad in Proof Viewer - Summer Sale of Shoes commenting and markups

Wireframe markups 

Web designers use wireframe annotation tools to explain how an on-screen feature should work. A wireframe annotation includes details about what you don’t see in a static image—for example, how an image carousel will display on a website.

You can use wireframe annotations to guide internal teams, like your developers and copywriters, plus clients, so everyone involved can provide feedback.

Compliance review

Marketers working in the healthcare, pharmaceuticals, and wellness sectors must ensure their creative content meets internal and external compliance guidelines. Failure to do so can result in hefty fines.

PDF annotations allow compliance personnel to review and approve all types of campaigns. 

PDF Annotations tool of Ziflow online collaboration platform - Vitamins complete pack photo being reviewed

Companies with strict brand guidelines can also use PDF annotations in their review and approval process.

Catalog and magazine review

Digital and print catalogs and magazines have several review stages. Reviewing multiple pages is tricky, especially center spreads with images and words that span two pages. But when you save all pages as a single PDF file, you can toggle back and forth and propose suggestions and changes with annotations. 

Online PDF review is particularly useful for high-volume print jobs where you’re checking and comparing details such as the colors, text registration, and image resolution. 

Magazine View It's time for a new adventure - Ziflow pdf markup tool

How to mark up a PDF - Top features for quality PDF annotator 

Here are the key ways your team can markup a PDF. You should make sure whichever PDF annotation softwares you consider have these features available.

Color accuracy and comparison

When you convert a PDF file into a proof, many PDF annotation tools cannot reproduce the true colors. Some tones can appear darker or lighter, or the color separation is inaccurate.

Maintaining color accuracy on a PDF proof is important because it ensures that designers, creative teams, and clients are looking at the right version of an asset. Eliminating confusion about the true appearance of design elements streamlines the review and approval process.

Image transparency 

ghent workgroup other online proofing vendor results on image transparency

Image transparency is another common element in many designs. But not all tools can accurately render transparency, which means reviewers can’t see a true representation of the original design. 

Measurement tools for formatting and printing

Measurement tools that let you review files down to the pixel, millimeter, or inch are the best way to check page size, bleed size, or the size of an object on a proof.

measurement tool in Ziflow online proofing collaborative software

With these tools, reviewers can accurately review what a file will look like at print, which helps clients avoid costly erroneous print runs. 


Highlighting allows you to draw attention to specific text or design element. For example, you might want to highlight text that should be larger or a different color. Highlighting provides precision in the review and feedback process.

Leaving a comment in a proof showcase in Ziflow animation

Strikethrough functions 

If you want to remove any text, you’ll need a strikethrough function to indicate what to remove.

strikethrough function in Ziflow presentation

Comment placement 

Any comments you make must align to the correct part of the PDF so that the designer or reader can apply changes correctly in the next version.

For example, this is how design agency MRM Global uses PDF annotation and commenting tools to review PDF documents for its clients' events and menus. 

comments mrm global - pdf annotation and commenting tools from ziflow

Conversation and version history 

All parties involved in your review and approval process should be able to follow the conversation and comment history sequentially, see who requested changes, and the details of those changes. 

version comparison tool in Ziflow software - with commenting toolbars on the sides

Upload and load speeds

PDFs often include many pages in one document. Uploading and loading these large files can tax certain software and PDF tools, and slow load speeds can delay the review and approval process. Make sure your annotation software can process and load PDFs quickly. 

Automated approval workflows

Finally, check that your PDF annotation software includes automated approval workflows with notifications, so stakeholders know when they need to review PDF files and your team knows when clients have left feedback and approved changes.

Stage approvals are especially critical for PDFs that contain a lot of information or require several rounds of review, such as legal documents. 

Workflow templates

Workflow templates help streamline repeatable PDF review processes. For example, a print shop doing several high-volume projects can apply a PDF review workflow to automate the design and review steps across projects. 

PDF Workflow templates - Ziflow feature to workflows

Automatically convert other files to PDF for review

Look for a tool that can convert other types of media to PDF for review. This is useful if you have a number of wireframes or other design files from the Adobe Creative Suite that you want to convert into one or several PDFs.

You can combine PDF conversion options with automated approval workflows to convert files from other applications or formats into PDFs, automatically put them in project folders, and initiate the right review workflows. 

Not all PDF annotation tools will meet the full needs of creative collaboration, so it’s important to weigh up the benefits and see which software fits your requirements. 

Annotation capabilities, processing speed, color accuracy, version comparison, conversation history, and automated approval workflows are all important features for PDF review and approval, especially for organizations that handle a high volume of PDF assets every day.

Read More: How Dynamicard Modernized the Direct Mail Campaign Launch Process

Learn how a high-volume print shop used PDF annotation to accelerate project deadlines and client review.

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