Article Summary
Most teams redline documents in whatever tool they already have open — usually Word or Google Docs. That works fine for a short memo. It breaks down fast on a 200-page technical manual with diagrams, multiple reviewers, and translated versions. Below, we compare the tools manufacturers actually use to redline documents, and where each one starts to struggle once the document gets complex.
Redlining is the process of marking up a document to show proposed changes — additions, deletions, and edits — so reviewers can see exactly what’s different from the previous version. Almost every collaboration tool claims to support it in some form. Not all of them hold up once the document is long, technical, or needs to go through translation.
We redline technical manuals for a living, so we’ve used, tested, and cleaned up documents from nearly every tool on this list. Here’s the honest breakdown.
Microsoft Word (Track Changes)
Word’s Track Changes is the most common redlining tool in the world, and for good reason: it’s built into software almost everyone already has, and reviewers understand it instantly.
Where it works well: Text-heavy documents with a small number of reviewers working one revision at a time.
Where it falls short: Track Changes gets messy fast with more than two or three reviewers editing the same section. Comments and tracked edits can overlap in confusing ways, and formatting changes (fonts, spacing, page breaks) often get flagged as “changes” even when the actual content didn’t change. It also doesn’t handle embedded diagrams, exploded views, or CAD-based illustrations at all — those have to be tracked manually, outside the document.
Google Docs (Suggesting Mode)
Google Docs’ Suggesting mode is Track Changes’ cloud-native cousin. Multiple people can suggest edits in real time, and everyone sees the same live version.
Where it works well: Fast-moving collaborative drafts with a small team, especially when reviewers are in different locations.
Where it falls short: Once a document has heavy formatting (numbered technical steps, tables, embedded images), Google Docs starts to lose fidelity — spacing and layout can shift unexpectedly. It also has no native way to compare two entirely separate versions of a document side by side, which matters when a manual has gone through several rounds and you need to see the full change history, not just the latest suggestions.
Adobe Acrobat (PDF Markup and Compare)
Acrobat’s Compare Files tool and its markup/commenting features are popular once a document is finalized as a PDF — which is how most technical manuals ship.
Where it works well: Comparing a final, formatted PDF against a previous final version, and collecting sign-off comments from stakeholders.
Where it falls short: Acrobat compares visual differences well, but it’s not built for drafting — you can’t easily restructure content or rewrite full sections inside a PDF the way you can in a word processor. It’s a great last step, not a great place to do the actual editing.
Bluebeam Revu
Bluebeam is popular in engineering and construction for markup on drawings and spec documents, and some manufacturers use it for technical documentation too.
Where it works well: Documents with heavy diagrams, drawings, or CAD-based content where markup needs to sit directly on a visual, not just in text.
Where it falls short: Bluebeam is powerful but has a real learning curve, and it’s licensed per user, which gets expensive if you need occasional reviewers (like a plant manager who only needs to approve one manual a year) to have access.
Dedicated Document Management / Redline Software
Purpose-built platforms exist specifically for version control and redlining at scale, often used by legal and compliance teams.
Where it works well: Organizations that need a strict audit trail — who changed what, when, and why — across many documents and reviewers.
Where it falls short: These platforms are usually overkill (and over-budget) for a single manufacturer managing product manuals, especially if the documents also need translation into multiple languages, which most dedicated redline platforms don’t handle at all.
The Common Thread
Every tool on this list is good at part of the problem. None of them handle the full picture that most manufacturers actually deal with: a manual that needs redlining, document production and formatting fixes, multi-reviewer sign-off, and translation into several languages — all while staying in sync with the last approved version.
That’s usually the point where teams either build a patchwork of three or four tools together, or bring in a partner who already manages that whole workflow end to end.
Related Resources
- Redline Documents: Our Redlining Service
- Creating Technical Manuals: Owners, Operators, Parts & Service Manuals
- Document Production Services
- Technical Writing Services
Frequently Asked Questions
What is the best tool for redlining a document?
It depends on the document. Word Track Changes and Google Docs Suggesting mode work well for text-heavy drafts with a few reviewers. Adobe Acrobat works well for comparing finished PDFs. Bluebeam works well for diagram-heavy or CAD-based documents. Most technical manuals need more than one of these tools across the process.
Can Google Docs handle redlining for technical manuals?
Google Docs works well for early drafts and fast collaboration, but it can lose formatting fidelity on documents with heavy tables, numbered steps, or embedded images, and it has no built-in way to compare full document versions side by side.
What’s the difference between redlining and track changes?
Redlining is the general practice of marking up proposed changes to a document. “Track Changes” is Microsoft Word’s specific built-in feature for doing that. Other tools use different names, like “Suggesting” in Google Docs, for the same basic concept.
Do I need special software to redline a PDF?
You can add comments to a PDF with free tools, but comparing two full versions of a PDF and tracking substantive changes usually requires a dedicated tool like Adobe Acrobat’s Compare feature.
When does it make sense to bring in outside help instead of managing redlines in-house?
When a document needs to go through multiple rounds of technical review, get translated into other languages, and stay perfectly in sync across every version, most in-house tool combinations start to break down. That’s usually the point where a dedicated documentation partner becomes more efficient than juggling several tools internally.