Summarize a confidential document with an AI, without sending the names
Paste the memo, report or note below, or drop it as a Word file. People, companies and references become codes; figures, dates and decisions stay readable. Ask the AI for a summary, key points or a briefing on the coded version, then restore it here: the summary comes back with the real names.
Restoring uses the key of this tab: code your text here first, keep this tab open, then come back with the answer.
Adjust
See the key (it stays in this tab)
The key links each code to the real value. It exists only in this tab's memory: close or reload the tab and it is gone.
connect-src 'none' in its security policy) and loads no analytics. Turn Wi-Fi off once the page has loaded: the tool works just the same. The engine is the one inside the Hidden Tokens app.How it works
1 · Code
Paste a text or drop a file. Names, companies, addresses, emails, phone numbers, bank details, ID and case numbers become codes such as NAME-001 or COMPANY-001. Unknown proper nouns are coded too: when in doubt, the engine codes.
2 · Send the codes
Copy the coded text, or download the coded file, and give it to ChatGPT, Claude, Gemini or Copilot. The AI reasons on the codes: it still knows who did what, not who they are.
3 · Restore
Paste the AI's answer in the Restore tab, in the same browser tab. The codes become the real names again, on your screen only.
Example: a board memo about an acquisition
Board memo (confidential), 4 November 2026
Subject: proposed acquisition of Larchmont Analytics Ltd
The founder of Larchmont Analytics Ltd, Dr Priya Venkatesan, has agreed in principle to sell 100% of the shares for £3.8m. Two senior engineers, Owen Treharne and Sasha Petrova, would receive retention bonuses of £60,000 each. Due diligence by Coleridge Hart LLP should finish on 15 December.Board memo (confidential), 4 November 2026
Subject: proposed acquisition of COMPANY-001
The founder of COMPANY-001, Dr NAME-001 NAME-002, has agreed in principle to sell 100% of the shares for £3.8m. Two senior engineers, FIRSTNAME-001 NAME-003 and FIRSTNAME-002 NAME-004, would receive retention bonuses of £60,000 each. Due diligence by COMPANY-002 should finish on 15 December.The target company, its founder, the two engineers and the law firm are coded; the price, the bonuses and the deadline stay readable for the summary. The tool also warns that “founder” plus a precise date can point to one person.
Summaries are safe to code, with one limit
Summarising is the task where coding costs least: a summary is about what happened, the amounts and the next steps, and the AI does that just as well with COMPANY-001 as with the real name. Restored, the summary reads as if the AI had seen everything.
- Ask for codes in the answer. Tell the AI to keep codes such as
NAME-003exactly as written. Most do it unprompted; asking avoids “Name-003” in a heading. - Watch the clues. A code name for a deal, a rare job title or a precise date can say who is involved. The tool flags some of them; read the coded text before sending.
- Long documents. The free tool codes up to 3,000 words at a time, and each coding starts a new key:
NAME-001in the second part may be someone else, and the first part's answer can no longer be restored. Summarise and restore one part at a time, then combine the restored summaries yourself.
For long reports or many documents, the Hidden Tokens app codes whole files and folders with one key, so the AI can summarise everything at once and the same person keeps the same code throughout.
The free tool or the Hidden Tokens app?
This free tool
- One text or one file at a time
- Up to 3,000 words or 1,000 spreadsheet rows
- The key lives in this tab and disappears when you close it
- Word, Excel, CSV and text
The Hidden Tokens app
- Whole folders: the same person keeps the same code in every document
- One key per case file, kept on your computer
- PDF and scanned documents, read on your computer
- Inside Claude Desktop, and in ChatGPT, Gemini and Copilot with the extension
- Industry packs, firm rules and a signed proof of what the AI saw
A word on the word “anonymize”
Strictly speaking, this tool pseudonymizes: each value is replaced by a code that can be reversed with the key. Under the GDPR, pseudonymised data is still personal data for whoever holds the key, which here is you, in this tab. What the AI receives no longer names anyone directly. Clues can remain, such as a job, a town and an age together: the tool warns you when it sees them. Read the result before sending it.
Questions
Does a coded summary lose quality?
Rarely. Figures, dates, decisions and the relationships between people stay intact; only identities are replaced. Restored, the summary has the real names.
My document is longer than 3,000 words. What can I do?
Code, summarise and restore one part at a time in this tab, since each coding replaces the key. The Hidden Tokens app has no length limit and keeps one key for a whole folder.
Can I drop the Word file?
Yes. The Word or Excel tab gives a coded .docx, layout kept and metadata removed, which you can attach to the AI.
What if the AI rewrites a code?
The Restore tab counts the codes it could not restore so you can fix them by hand. Asking the AI to keep codes as written prevents most cases.
Other ways to use the free tool
By file type
By AI tool
By task
For whole folders, use the app
Hidden Tokens codes whole case files on your computer with one key, works inside Claude Desktop and in your browser, reads PDFs and scans, and puts the real names back into Word and Excel files.