Can ChatGPT Compare Legal Documents? Now It Can, With the Litera Plugin
Yes. As of Nov. 3, 2026, lawyers can compare legal documents in ChatGPT and get a true redline, using the Litera Plugin for ChatGPT. The plugin runs the Litera comparison engine, the redline standard for 67% of the legal market (ILTA 2026 Technology Survey) and 99% of the Am Law 100, so every change is detected, not predicted.
That matters because ChatGPT on its own can’t do this. When a counterparty’s draft comes back, a general model summarizes what it thinks changed. It can miss edits in tables, headers, and footnotes, and it can’t produce a redline anyone can send. Lawyers end up checking the AI’s answer and the document at the same time.
The Litera Plugin for ChatGPT already brought Firm AI Search into ChatGPT, so lawyers could ask who has done the work and where the experience sits. Today it adds comparisons. From the redline to the next pitch, lawyers never have to leave the assistant they already use.
What Is the Litera Plugin for ChatGPT?
The Litera Plugin for ChatGPT connects ChatGPT to the Litera capabilities a legal team has licensed. Lawyers sign in with their Litera account and can do two things without leaving ChatGPT:
- Compare documents. Upload two or more versions, ask for a comparison, and get a redline from the Litera comparison engine.
- Search their own experience. Firm AI Search answers who has done this work, on which matters, and where the experience sits.
Can ChatGPT Redline a Contract?
On its own, no. ChatGPT predicts what changed between two documents and describes the differences in prose. That works for a quick read, but a redline is the record that goes to a counterparty, so it has to be complete and exact.
In Litera benchmark testing, general-purpose models struggled as documents got longer and more complex:
| Test | General-purpose AI | Litera comparison engine |
|---|---|---|
| Tables, images, headers, and footnotes | No redline produced | Every change redlined |
| 200-page document, text changes | About 40% to 70% accurate | Stable precision as length grows |
| What lawyers receive | A summary of changes | A true redline document |
The difference is how the work gets done. A general model is probabilistic: it estimates. The Litera engine is deterministic: it applies rules refined over 30 years of legal comparison to detect every change, the same way every time.
How Do I Compare Two Documents in ChatGPT?
- Ask your Litera administrator to turn on the Litera Plugin for ChatGPT in Litera Admin Center.
- Add the plugin in ChatGPT and sign in with your Litera account.
- Upload the original and the revised document, and ask ChatGPT to compare them.
- Review the redline, ask for a plain-language summary of what changed, or download the result.
The comparison runs on the same engine lawyers already use in Litera for Word, Outlook, and the web, so the redline in ChatGPT matches the one they would get anywhere else.
What’s New in This Launch?
Firm AI Search arrived in ChatGPT first, giving lawyers a plain-language way to find who has done the work before. This launch adds comparisons, the task lawyers run most. Together they cover the full arc of a matter: Firm AI Search helps win the work, and the comparison engine helps negotiate it.
Who Can Use the Litera Plugin for ChatGPT?
- Comparisons are included on Pro and Advanced plans across Litera’s packages.
- Firm AI Search is available as early access to Litera Foundation customers as part of their Foundation subscription.
There’s nothing new to sign for customers already on those plans. The plugin appears as a new option in Litera Admin Center.
Is It Secure?
Each user signs in with a Litera account and sees only the capabilities their subscription includes. Administrators decide who can use the plugin and when to turn it on.
Be First in Line
Your lawyers are already working in ChatGPT. Now the redline can be there too. Sign up for the rollout list, and our team will work with you to bring the Litera Plugin for ChatGPT to your firm or legal department: Sign up for the rollout list
Frequently Asked Questions
What is the most widely used document comparison software for law firms?
Litera Compare is the redline standard for 67% of the legal market and is used by 91% of firms with 700 or more lawyers, according to the ILTA 2026 Technology Survey.
Is the redline in ChatGPT the same as in Litera for Word?
Yes. The plugin runs the same deterministic Litera comparison engine, so lawyers get the same redline in ChatGPT that they get in Word, Outlook, and the web.
Does the plugin replace Litera Compare?
No. It brings Litera Compare into ChatGPT, so lawyers can run comparisons wherever they start their work.
Can the plugin compare tables, headers, and footnotes?
Yes. The Litera comparison engine detects changes in text, tables, images, headers and footers, and footnotes.
Do lawyers need to learn a new tool?
No. They stay in ChatGPT and ask in plain language. The redline comes from the Litera engine they already trust.
