Data Anonymizer

Mask sensitive data (emails, names, phones, SSNs, credit cards) in CSV, JSON, or SQL. Add custom regex rules for any pattern. All processing happens in your browser.

How to use:

  1. Upload a .csv, .json, or .txt file — or paste data directly
  2. Select which data types to mask using the checkboxes
  3. Toggle 'Realistic fake data' for format-preserving anonymization
  4. Click "Anonymize Data" to apply masking rules
  5. Copy or download the anonymized output for safe testing
4 rules active

Masking Rules

4 active

Add Custom Rule

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Input Data (CSV / JSON / SQL)

Anonymized Output

Click "Anonymize Data" to see results.

About this tool

Data Anonymizer is a free privacy tool that masks sensitive information — emails, phone numbers, credit cards, IP addresses, and more — in CSV, JSON, or SQL data. Built-in rules cover common PII patterns, custom regex rules handle anything else, and optional realistic fake data keeps output format-valid for testing.

Input
Pasted or uploaded CSV, JSON, or SQL text
Output
Anonymized data in the same format, ready to copy or download
Built-in rules
Email, phone, credit card, IP address — each toggleable
Custom rules
Any pattern via regular expressions
Mask modes
Full mask, partial mask (first/last characters), or format-preserving realistic fake data
Signup
Not required
Processing
Entirely in your browser — your data is never uploaded for processing, which is what makes it suitable for sensitive data
Price
Free

Limitations

  • A utility for preparing test/demo datasets — not a compliance or data-governance product.
  • Pattern-based masking: values that do not match an enabled rule are left unchanged.