CSV Anonymizer

Protect privacy before sharing or testing data. Upload any CSV, auto-detect PII columns (names, emails, phones, addresses, IBANs, IP addresses), choose replacement strategies per column (fake value, hash, redact, blank, index), and download the clean result instantly. Consistent replacement ensures the same source value always maps to the same fake value within a session, preserving relational integrity across rows. All processing happens client-side — your data never leaves the browser.

Auto PII Detection 7 Anonymization Strategies Consistent Mapping Column-by-Column Control 100% Client-Side

SECURE

Protected Connection

Anonymize customer export before sharing with contractor

Replace production emails/phones with fake data for QA

Hash user IDs to preserve counts without exposing identity

Trust Score

5.0

Upload CSV File

Drop CSV here or click to browse

Max ~50 MB · UTF-8 or Latin-1 · comma or semicolon separated

Delimiter

Encoding

Sample Datasets

No CSV handy? Load a sample to explore the tool instantly.

Columns 0

Global Options

Default strategy for selected columns

Consistent mapping (same input → same output)

Preserve original column headers

Upload a CSV or load a sample dataset to get started.
Your data never leaves your browser.

Preview

Export Anonymized CSV

Output delimiter

Filename

Help & Related Tools

Everything you need to know

FAQ Frequently Asked Questions

What PII types does the tool detect automatically?

The auto-detector scans column headers and sample values for names, email addresses, phone numbers, street addresses, postal codes, dates of birth, IBAN numbers, IP addresses, and national ID patterns. You can override or extend any detection manually.

Is my data uploaded to a server?

No. The entire process runs in your browser using JavaScript. Your CSV file is never sent to any server. You can even use this tool offline after the page has loaded.

What does consistent mapping mean?

Consistent mapping means the same original value always receives the same fake replacement within a session. For example, if "john@example.com" appears in 50 rows it will always be replaced by the same fake email, preserving row relationships and counts.

What anonymization strategies are available?

You can choose per column: Fake Value (realistic placeholder), Hash (SHA-256 prefix), Redact (fixed string like [REDACTED]), Blank (empty string), Index (PERSON-1, PERSON-2…), Partial Mask (jo***@***.com), or Keep Original (no change).

How large a CSV file can I process?

The tool handles files up to around 50 MB comfortably in modern browsers. Larger files may cause a short processing delay. There is no hard server-side limit because everything runs locally.