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Document Anonymizer

Strip names, SSNs, emails and 20+ PII types from any document β€” entirely in your browser. Nothing is uploaded.

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Drop a PDF, Word, or .txt file β€” or paste text below
Everything runs locally. Your document never leaves this tab.
1 Β· Paste or load your text
2 Β· Choose what to redact
Placeholder style:

This tool finds patterns, not meaning. It reliably removes structured identifiers and labelled names, but no automated tool catches everything β€” always review the output before you rely on it. This is not legal advice.

What the Document Anonymizer Does

The Document Anonymizer scans a contract, letter, pleading, or any block of text and replaces personally identifiable information with neutral, typed placeholders. Drop in a PDF or Word file, or paste text directly, and within a second every email address, Social Security number, payment-card number, phone number, street address, court case number, and labelled name is swapped for a token like [PERSON_1] or [SSN_2]. The result reads like the original document with the identities lifted out β€” close enough to share with a vendor, attach to a support ticket, post in a forum, or hand to an AI model for analysis, but stripped of the details that identify real people. The entire process happens inside your browser tab, which is the whole point: a confidential agreement is the last thing you want to upload to a stranger's server just to clean it up.

Why a Browser-Only Tool Beats the Upload-Based Alternatives

Most free redaction sites ask you to upload your document so a server can process it β€” which means the very file you are trying to protect is transmitted, queued, and processed on infrastructure you do not control, often behind a monthly limit of two or three documents. That model is backwards for confidential material. This tool inverts it. There is no upload, no queue, no account, and no per-document cap. The JavaScript that detects and replaces PII is delivered to your browser once and then runs locally on whatever you give it, however many times you like. For anyone bound by confidentiality or data-minimization rules β€” lawyers, paralegals, HR staff, founders reviewing their own agreements β€” the local-only design is not a nice extra; it is the feature. If you also need to remove hidden authorship data, pair this with the DOCX Metadata Inspector to see what a Word file is carrying before you send it.

Redacting Before You Paste Into ChatGPT or Claude

The fastest-growing reason people reach for a redactor in 2026 is to clean a document before feeding it to an AI assistant. Pasting a raw contract into a chatbot to ask "what are the termination penalties?" can send a client's name, address, and financial figures into a third-party model that may log the input or surface it during human review. Anonymizing first solves this cleanly: because each distinct identity maps to a consistent placeholder, the model can still reason about who owes what to whom β€” [PERSON_1] indemnifies [PERSON_2] β€” without ever seeing the real parties. You get the analysis; the personal data stays on your machine. When you want to compare two versions of an agreement rather than de-identify one, the Contract Redline tool shows a word-level diff, also entirely in-browser.

Consistent Placeholders Keep the Document Readable

A redactor that blacks out every name independently destroys the thread of a document β€” you can no longer tell whether the buyer or the seller bears a given obligation. This tool avoids that by mapping each distinct value to a stable token. The first party detected becomes [PERSON_1] and stays [PERSON_1] at every mention; a different party becomes [PERSON_2]. The same is true for emails, addresses, and every other category. There is also a literal-occurrence sweep: once a name is identified anywhere β€” say, in a signature block β€” every other appearance of that exact name in the body is caught too, even where no label flagged it. You can switch between bracketed placeholders, which preserve readability and structure, and solid block characters for a more traditional redacted look. For removing identifying data from images rather than text, the Image Metadata Stripper clears EXIF and GPS tags from photos.

Honest Limits: Patterns, Not Judgment

It is worth being plain about what a deterministic tool can and cannot do. This anonymizer recognizes information by its shape and its context, not by understanding the document. Structured identifiers β€” emails, SSNs, Luhn-valid card numbers, IBANs, IP addresses, case numbers β€” are caught reliably because they have distinctive formats. Names are caught when they appear with a label ("Client:", "Tenant:"), a title ("Dr.", "Ms."), or a signature cue, and then swept across the rest of the text. What it can miss is a bare name dropped into a sentence with no surrounding signal, an identifier in an unusual format, or sensitive information that is implied rather than written out. That is a deliberate trade-off: catching every capitalized word would also redact ordinary language and make the output unreadable. The right workflow is to run the tool, then read the result and catch anything it left β€” especially for court filings or regulated disclosures, where you remain responsible for the final document. A scanned PDF with no text layer also can't be read directly; send it through the PDF OCR tool first, then anonymize the recognized text.

Frequently Asked Questions

Is my document uploaded to a server?+
No. Everything runs inside your browser tab using JavaScript. The file you drop or the text you paste is read into memory locally, scanned, and redacted on your own device. Nothing is transmitted to any server, and there is no account or sign-up. This is the core reason to use a client-side tool for sensitive contracts and legal documents β€” the confidential text never leaves your machine, so there is no upload to log, leak, or retain.
What kinds of information does it detect?+
It detects around two dozen categories: full names (from labels, titles, and signatures), email addresses, phone numbers, Social Security numbers, payment-card numbers (Luhn-validated), bank IBANs, EINs, IP addresses, web addresses, street addresses, ZIP and postal codes, dates, monetary amounts, court case and docket numbers, bar and license numbers, and vehicle identification numbers. You can toggle any category on or off before redacting so you only remove what you intend to.
Does the same name get the same placeholder everywhere?+
Yes. Each distinct value is mapped to a stable typed placeholder, so a party named once in a header is replaced with the same token, like [PERSON_1], every time that exact name appears in the document. A second party becomes [PERSON_2], and so on. This consistency is what keeps the redacted text usable: an AI tool or reviewer can still follow who did what to whom without ever seeing the real identities.
Why would I redact a contract before pasting it into ChatGPT or Claude?+
AI providers may log, retain, or have humans review the text you submit, and sending a client's name, SSN, or financial details into a third-party model can breach confidentiality and data-minimization obligations. Replacing identifiers with typed placeholders first lets you get the AI's analysis of the clauses, obligations, and structure without exposing anyone's personal data. Because this tool runs locally, the masking step itself also never sends the document anywhere.
Can it read PDF and Word files, or only pasted text?+
All three. You can paste text directly, upload a plain-text (.txt) file, or drop a PDF or Word (.docx) document. PDF text is extracted in-browser with pdf.js and Word text with mammoth.js β€” both run locally, so the file is never uploaded. Note that a scanned PDF is an image with no text layer; run it through the PDF OCR tool first to add recognized text, then anonymize the result.
Is this the same as visually blacking out a PDF?+
No, and the difference matters. Drawing black boxes over a PDF often leaves the underlying text selectable and recoverable beneath the box. This tool replaces the actual characters with placeholder tokens in the extracted text, so there is no hidden original underneath. If you specifically need to box out regions of a visual PDF while keeping its layout, use the PDF Redactor; if you need clean de-identified text to share or analyze, use this tool.
Will it catch every piece of personal information?+
No automated tool should be trusted to catch everything, and this one finds patterns, not meaning. It reliably catches structured identifiers like emails, SSNs, and card numbers, and catches names that appear with a label, title, or signature cue. It can miss a bare name with no surrounding context, an unusual identifier format, or information implied rather than stated. Always review the redacted output before relying on it, especially for court filings or regulated disclosures.
Can I download the redacted document or get a summary of what changed?+
Yes. The redacted text appears on the page where you can copy it with one click or download it as a .txt file. Alongside it, a redaction report lists how many items were removed in each category and how many distinct values were mapped, so you have a quick audit of what the tool changed before you share the result.
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