The 6 best PDF comparison tools on the market in 2026

Comparing PDF files to find changes can be a drag. Especially when you’re working on a lengthy document. Skimming the files and flicking between the two can feel like a poorly organized, never-ending game of spot the difference.

Then there’s the matter of making sure everyone’s feedback has been implemented. And when there are dozens of comments from a whole host of stakeholders, it can feel like Mission Impossible. 

That’s where PDF comparison tools come into play. 

With the right software, you can compare two PDFs – complete with comments – side by side. The best tools will automatically highlight any differences, helping you to see exactly what’s changed.

So with that in mind, let’s take a look at how we evaluated the six best tools for comparing PDF files.

How we evaluated these tools

We assessed these six tools based on how accurately each one detects changes between document versions, whether it tracks reviewer comments alongside the comparison, how it handles different file formats, and how its pricing stacks up against the value it delivers. For simpler free tools, ease of use and speed mattered most; for full platforms like Filestage, we focused on how well they support structured review workflows beyond basic comparison. We’ve also flagged where each tool falls short and when a different one on this list would be a better fit.

Filestage is our product. We’ve included it in this list because it genuinely fits the use cases described, and we’ve positioned it accordingly.

All pricing was checked in July 2026 and may change.

The 6 best PDF comparison tools at a glance

1. Adobe Acrobat – best for Adobe and enterprise users

Windows users might already be familiar with Adobe Acrobat, as it’s the pre-installed PDF viewer on most Windows devices. With its Pro version, you can compare two PDFs and get an automatic report marking every insertion, deletion, and replacement.

Why we chose it

What sets Acrobat apart from the cheaper tools on this list is the content-type filter: you can isolate exactly what kind of change you want to review, such as text only, image changes, annotation differences, or formatting shifts, rather than wading through everything at once. That level of control is useful on complex, multi-element documents. If file comparison is the only thing you need and you’re not already paying for Acrobat, there are faster and cheaper options lower down this list.

Pros

• Filter by content type — view text, image, annotation, or formatting changes in isolation
• Strong performance on complex, multi-element documents that text-only tools struggle with
• Tight integration with Microsoft apps and the broader Adobe Creative Suite
• Widely recognized as the industry standard, which matters in legal or regulated contexts

Cons

• Comparison is a Pro feature — the free Adobe Reader doesn’t include it
• At $19.99/month, it’s the hardest subscription to justify if you only need comparison and aren’t using the rest of the Acrobat suite

Pricing

• Acrobat Pro for teams: $23.99/month per license (billed annually)
• Acrobat Pro individual: $19.99/month (billed annually)

2. Filestage – best for comparing PDF versions in a review and approval workflow

Filestage is a review and approval platform that makes it easy to compare and proof PDF files and compare versions side by side, with changes highlighted automatically and previous reviewer comments visible alongside each version. It’s also a PDF markup tool, allowing reviewers to annotate, highlight, and leave comments directly on the file, which is what makes the comparison useful rather than just visual. 

Why we chose it

It’s the only tool on this list where the comparison and the review record live in the same view: you can see what changed between two versions, what feedback prompted the change, and whether it’s been addressed, without switching to email or another tool. That makes it the right pick for teams running a structured approval process rather than a one-off check. It brings more infrastructure than some users will need, so it’s worth thinking about whether the broader workflow earns its place. 

“The commenting feature in Filestage allows all project stakeholders to give open and transparent feedback, making it easy for each party to understand document change requests.”

Tim Simonsen, Marketing Director at Queisser Pharma GmbH & Co. KG – Doppelherz

Pros

• Cross-format comparison: upload one PDF and one Word document and compare them directly without converting either file
• Click any comment in the older version to jump to that exact point in the document
• Auto-compare text produces a searchable list of every textual change between versions
• Supports all file types, including designs, videos, and other formats in the same platform

Cons

• More than you need for a one-off check — iLovePDF or Diffchecker are faster and free for that
• Browser-only: no desktop app, so you need an internet connection to use it

Pricing

• Free plan – 1 active project, 5 files per month, unlimited reviewers, no comparison features included
• Starter plan – $199/month, includes unlimited projects and files, plus basic version comparison, due dates, and reminders
• Business plan – $329/month, includes advanced compare mode, Review Agents, project templates, and automations
• Enterprise plan – Custom pricing (contact sales)

3. Draftable – best for comparing formatting

Draftable is a document comparison tool that tracks formatting changes (font, size, bold, italics) alongside content changes, compiling every difference into a clickable list. It supports PDF, Word, Excel, and PowerPoint.

Why we chose it

Most comparison tools only flag content differences. Draftable flags both, which matters when you’re reviewing branded materials, legal documents, or anything where a change in font size carries the same significance as a change in wording. It’s deliberately focused, with no annotation tracking or approval workflow, which keeps it fast and simple for the specific task it’s built for. For anything involving multi-stakeholder feedback, you’ll need a different tool.

Pros

• Catches font, size, and style changes that content-only comparison tools miss entirely
• Handles PDF, Word, Excel, and PowerPoint comparisons in a single workflow
• Every change is compiled in one list with click-through navigation to each point in the document

Cons

• No comment or annotation tracking, so you can see what changed but not who flagged it or why
• Desktop app is Windows only; Mac support is listed as coming late 2026

Pricing

• Desktop app: $129/year per user
• Free online version (with page and file size limits)

4. Soda PDF – best for low-cost PDF comparison

Soda PDF is an all-in-one PDF platform that highlights differences between two documents side by side. It runs on web for both Mac and Windows, with a desktop app also available for Windows users.

Why we chose it

Soda PDF makes this list on value. At $10.27/month, the Pro plan bundles comparison into a full PDF editing suite that also covers conversion, redaction, OCR, and signing. That makes it a practical choice for anyone who needs more than a diff-checker and wants to avoid paying for multiple tools separately. The comparison feature is content-focused rather than workflow-focused, which is worth knowing upfront.

Pros

• Bundles PDF comparison with a full editing suite, covering conversion, redaction, OCR, and signing in one subscription
• One of the lowest price points on the list for a paid tool with this breadth of features
• Works on both Mac and Windows via the web, with a Windows desktop app for offline use

Cons

• No comment or annotation tracking, so changes are highlighted but previous reviewer feedback isn’t visible in the comparison output
• Some users report intrusive ads and pop-ups in the desktop version

Pricing

• Pro plan: $10.27/month billed annually
• Free trial available

5. Diffchecker – best free tool for comparing basic PDF files

Diffchecker is a free online tool that converts PDFs to plain text and highlights differences line by line. No account required; it works immediately in the browser.

Why we chose it

Diffchecker earns its place as the most frictionless free option on this list. For a short, text-heavy document where you need a quick spot-check before signing off, nothing here is faster or easier to access. It’s a text comparison tool by design, which is exactly what makes it good at the specific job it does and less suitable for anything more layered.

Pros

• Completely free with no account or signup, so you open the browser, upload, and get a result
• Desktop app available for more sensitive or offline work on paid plans
• Clean, easy-to-scan output for simple documents

Cons

• Converts PDFs to plain text before comparing, so formatting changes and layout shifts are invisible in the output
• Accuracy drops on longer documents or complex layouts with tables, images, or non-standard formatting
• No comment or annotation tracking

Pricing

• Free (web, with basic features)
• Pro + Desktop: $15/user per month
• Legal: $20/user per month
• Enterprise: $40/user per month

Want to see more like this? Check out our full roundup of the best file comparison tools.

6. iLovePDF – best free online PDF comparison

iLovePDF is a free online PDF toolkit with a dedicated compare feature. Upload two files, get a side-by-side highlighted comparison, and download the result with no account or signup required.

Why we chose it

Of the free tools on this list, iLovePDF produces the most visual, reader-friendly comparison output, with color-coded changes displayed side by side and downloadable as a PDF. The content overlay mode adds something the other free tools don’t: the ability to compare visual elements like layouts and images, not just text. It’s the right pick for a one-off comparison where speed and simplicity matter most. Before uploading, check whether your documents are suitable for third-party server processing.

Pros

• Most visual comparison output of the free tools here, with a color-coded side-by-side view and a downloadable report
• Content overlay mode compares layouts and image placement, not just text differences
• Files automatically deleted from iLovePDF’s servers after two hours

Cons

• No comment or annotation tracking, so the output shows differences only with no connection to reviewer feedback
• Files processed on iLovePDF’s servers, making it unsuitable for confidential or commercially sensitive documents

Pricing

• Free (comparison and core tools available without signup)
• Premium plan: pricing not publicly listed on iLovePDF’s website

How to choose the best PDF comparison tool for your needs

If you need a quick, one-off check and data sensitivity isn’t a concern, iLovePDF or Diffchecker get you there in under a minute for free. If formatting changes matter as much as content (font, size, and style in legal documents or branded materials), Draftable is the most thorough option for that.

For teams running a structured review and approval process, where knowing who asked for a change is as important as seeing whether it was made, Filestage is the only tool in the list that connects comments to the comparison. Adobe Acrobat Pro is worth considering if you’re already paying for Adobe licenses and need a step up from the free tools without committing to a full review platform.

How to compare PDF files with Filestage

With Filestage, document comparison and version control have never been easier. Not only can you auto-compare text to save time reviewing PDFs, you can also rest easy knowing everyone’s feedback has been met for the desired file.

Here’s how to compare files with Filestage.

1. Upload your PDF files

Create your project and upload the first version of your PDF. Then click “Upload a new version” and select file to add v2. The built-in file versioning feature will automatically stack your new version on top of the old one, keeping them neat, tidy, and easy to find.

2. Open the latest version and click ‘Compare’

Select the “Compare” text button that’s positioned at the top of the screen. By default, the system will open the two most recent versions. If you’d like to choose another version, you can choose it from the version menu on the top bar.

3. Compare versions and comments side by side

As you scroll through the two files, the highlighted sections signal where changes have been made. Each of these changes is linked to a specific comment. To check that you’re happy with each change, and to make sure that all previous feedback points have been actioned, scroll through the comments and click on them individually. This will automatically take you to the right place in the document. Tick off comments as you go so that you know for certain that everything’s good to go.

4. Auto-compare text to see a list of changes

Another way to run through the changes is to click ‘Auto compare text’ on the top bar. This will give you a list of all the changes. Click on them one by one to see them in situ.

The next step depends on where you are in the process. If further changes need to be made, action them and then upload v3. If everything’s good to go, submit your PDF file for another review. It may even be ready for approval!

Three best practices for comparing PDFs effectively

Here are three top tips for comparing PDFs and getting the most out of the process. 

1. Encourage reviewers to add comments and annotations directly on the PDF file

By giving reviewers a centralized place to leave feedback, you’ll keep everything in one place. Then when the time comes to compare files, it’s easy to make sure everyone’s comments have been addressed. No missed feedback. No angry stakeholders.

With Filestage, reviewers can leave precise comments and notes directly on the PDF file. They can also annotate the document with highlighting tools, shapes, and a free drawing tool, for clear and detailed feedback every time.

Find out more about the best feedback tools available right now.

2. Review changes systematically 

It’s a good idea to have a system in place when comparing two files, rather than taking the scattergun approach. That way, you can be sure you’ve checked everything. Start from the beginning and work through each change one by one.

With Filestage, you can tick off each comment as you go along to reduce the chance of missing any amends or feedback.

3. Use a PDF comparison tool

If there’s one thing you’ve learned from this article, it’s that the right tool can work wonders in helping you with document comparison. Save yourself time, effort, and potential human error by using a specialized tool like Filestage to do the hard work for you.

Side-by-side comparison. Highlighted differences. Feedback analysis. These features are all designed to streamline the comparison process and make sure that the final version of your PDF is as accurate as can be.

Final thoughts

We hope this article has given you everything you need to confidently compare files. With the right tool and the help of our tips, you should be well on your way.

If you’d like to see for yourself how Filestage can help you with PDF document comparison, make sure to start a free trial →

FAQs about PDF comparison