Which tool to choose
Here we're not talking about writing a novel: you need a tool that doesn't "embellish" by inventing clauses. Precision matters more than creativity.
- You have a contract in PDF or Word and want maximum fidelity → Claude. It analyzes long documents well, makes few mistakes in data extraction, and returns a file in .docx format. For a legal text, where changing one wrong word changes an obligation, it's the right profile. On the free plan you upload documents and analyze them; the exact size limits change over time, but for a contract of a few pages you don't come close.
- You want everything inside a tool you already use, and the contract is short → ChatGPT. It reads PDFs even on the free plan: you upload the file and ask questions, request summaries, have the key points extracted. The free plan, however, limits the number of daily uploads: enough for one contract, tight if you have many.
For both, the free version covers a contract of a few pages. The paid plan (ChatGPT Plus at $20/month) is only needed if you work nonstop on many documents.
How to do it
From a browser or from the app the path doesn't change: the key action is uploading the file and giving a precise instruction.
- Open a new conversation and locate the paperclip-shaped icon (or "+" sign) in the message bar. That's where you attach documents; the tool extracts the text, reads the tables, answers questions.
- Upload the contract. If you only have a photographed paper version, go to the "When it does NOT work" section: a scanned PDF must be handled separately.
- Paste this prompt:
You are a reviewer of legal texts. Rewrite the attached contract
in everyday Italian, understandable to someone who is not a lawyer,
respecting these rules:
1. Do not add, remove, or modify any obligation, right,
amount, date, or deadline. The legal meaning stays identical.
2. Replace archaic formulas and Latin with words in
common use (example: "ancorché" becomes "even if").
3. Break long sentences into short sentences, one idea per sentence.
4. Keep the numbering of the articles and the names of the parties.
5. For each article, below the simplified version add a
note in parentheses: "meaning unchanged" or, if you had
to interpret an ambiguous passage, "warning: point unclear
in the original, to be verified".
6. At the end, list the clauses that remain ambiguous or that could
disadvantage one of the parties.
Proceed article by article.
- Read the answer with the original open alongside. Check: if the AI changed an amount, a date, or "rounded" an obligation, you'll notice by comparing the two texts article by article. It's the check you can't skip.
- Refine with a second targeted message. A vague request produces a generic summary; a precise instruction extracts action points and dates. For example:
Article 4 on the penalty is still heavy: rewrite it more simply
without changing the figure or the conditions.
- Ask for the ready file:
Give me back the complete simplified version as a downloadable Word
document.
With Claude the delivery of the .docx is native; with ChatGPT, if it doesn't generate the file, copy the text into a document yourself.
A concrete example
Marta rents a room and receives from the owner a draft with lines like: "The lessee undertakes, even jointly and severally, to pay the rent at the agreed deadline, it being understood that any delay will entail the application of default interest at the legal rate."
She uploads the PDF to Claude (free), pastes the prompt above. For that article she gets:
"You (the tenant) commit to paying the rent by the agreed date. If you pay late, you'll have to add the interest provided by law. (Meaning unchanged.)"
And at the bottom, in the list of ambiguities, the AI flags: "Article 3 cites 'incidental expenses' without specifying which: ask the owner for a written list." Marta didn't even know that "even jointly and severally" didn't concern her in a contract with a single tenant. Now she has a text she understands and a precise question to ask before signing.
When it does NOT work (and how to fix it)
If the contract is a scan or a photo
If the PDF is the image of a sheet (text not selectable with the mouse), the AI may read it badly or skip lines. Convert the scanned PDF into text with an OCR before uploading it. Tools like Smallpdf or Adobe have a free "PDF to Word" that does the OCR (optical character recognition: turns the image into editable text). Then reread the extracted text, because OCR gets numbers and accents wrong: fix them by hand before passing it to the AI.
If the AI changes an amount or a date
It's the serious risk. A document can contradict itself between sections and attachments, and without an explicit request the model stops at the first plausible answer. Fix: after the rewrite, send this cross-check.
List in a table all the numbers, amounts, dates, and deadlines:
"original" column, "simplified version" column.
Flag every difference between the two columns.
Any discrepancy you'll see at a glance.
If the contract contains personal or confidential data
Name, tax code, IBAN, third-party data: they shouldn't be uploaded carelessly. Fix: before uploading, redact or replace the sensitive data with placeholders like "[NAME]", "[IBAN]". The legal sense of the clauses doesn't change and you work with peace of mind. If there's a lot of data, do the replacement first in the Word document with "find and replace."
If the contract is very long
A specification document or a notarial deed of dozens of pages can exceed what the model keeps in mind at once. Claude's context window covers several hundred pages: for normal cases it's plenty. If you exceed it, divide the document by articles or headings and work in blocks, then ask for an overall reread with this message.
I uploaded the contract in several parts. Reread the whole and flag
the clauses that reference or contradict each other between one block and another.
A tip from someone who really uses it
The AI simplifies the words, but it doesn't tell you whether the contract is good for you. The most useful thing isn't the rewrite: it's the final list of ambiguous or unbalanced clauses you asked for in the prompt. That turns passive reading into a list of concrete questions to ask the other party (or a real lawyer) before signing. A simplified text you sign without understanding the risks is worse than a difficult one that put you on alert.
Frequently asked questions
Does the simplified version have legal value?
No, in itself it's an aid to understanding, not a new contract. What's binding is what you sign. If you want the clear version to replace the original, it must be the one signed by both parties, and at that point it's better to have it checked by a lawyer, because even a comma shifts the meaning.
Can I trust that the AI hasn't changed anything?
Only after the cross-check. The model makes few mistakes in data extraction, but "few" isn't "zero": the original-vs-simplified table is your parachute. Don't skip it on numbers and deadlines.
ChatGPT or Claude for contracts?
For fidelity to the text and the Word output, Claude. For convenience if you already use it and the contract is short, ChatGPT. On a legal document precision weighs more, and there Claude has the advantage on long documents and on .docx export.
Is it worth paying for the subscription to do this?
Almost never, for occasional use. Don't upgrade in advance: start from the free plan, see if you reach the limits, and pay only when the friction is real. For one or two contracts a month, the free version of Claude or ChatGPT is more than enough; the subscription makes sense if you work on documents every day.
"A contract has to be written in legalese anyway, doesn't it?"
It's the myth to debunk. "Legalese" doesn't make a contract more valid: often it just serves to copy old templates without rethinking them. A contract in clear Italian is equally binding and reduces disputes, because both parties understand what they signed. Complication isn't a legal requirement, it's a habit, and it's exactly that habit the AI helps you dismantle.