As of 13 August 2026, AI can compare two versions of a contract.

What to actually do

1. Hand it to a person

   The route this page recommends

   A person who owns the outcome does this end to end, worth it when the failure is dear.

2. Use a tool built for this

   Second choice

3. Do it yourself

   The distant third

   A chat interface, chat-fluent skill, and roughly 30 minutes until you can act on the result.

   How to actually do it

   1. Open the original contract files and create clear copies labelled [OLDER VERSION NAME] and [NEWER VERSION NAME], keeping tracked changes and comments visible if they form part of the documents.
   2. Remove unnecessary personal data and commercially sensitive material where possible, while retaining the clauses, schedules, definitions, signatures and page references needed for a reliable comparison.
   3. Upload both files to a chatbot or contract comparison tool and paste the prompt exactly, replacing the two bracketed version names.
   4. Ask the tool to produce the clause-by-clause table and separate lists, then save the result with the two source files and the date of the comparison.
   5. Open each cited page and clause in both source files and check every reported addition, deletion, number, date, party name and cross-reference against the generated table.
   6. Mark changes involving liability, indemnities, termination, payment, intellectual property, confidentiality, data protection, governing law or unusual obligations, and send those changes with the original files to a UK solicitor before signing or relying on them.

   Prompt

   Compare the two attached contract versions for a UK business. Treat [OLDER VERSION NAME] as the older version and [NEWER VERSION NAME] as the newer version.
   
   Produce:
   1. A concise summary of the important changes.
   2. A clause-by-clause table with these columns: clause or page reference, older wording, newer wording, change type, and practical issue to check.
   3. Separate lists of additions, deletions, wording changes, moved or renumbered clauses, changed dates, changed figures, changed parties, changed obligations, changed termination rights, changed liability or indemnity wording, changed confidentiality or data protection wording, and changed governing law or jurisdiction.
   4. A list of anything that appears inconsistent, missing, unreadable or ambiguous.
   5. A short list of changes that should be escalated to a UK solicitor before signature or reliance.
   
   Copy the relevant wording exactly where possible. Do not silently correct spelling, fill gaps, infer missing text or treat a formatting change as a substantive change. Distinguish clearly between a textual difference and its possible practical effect. If a page, clause or word cannot be read, say so. Do not decide whether either version is legally valid, enforceable or suitable, and do not give legal advice. End by stating that the comparison must be checked against the original files and is not professional advice.

   Open it prefilled in ChatGPT or Claude, or copy it into Gemini, which takes no prefill link.