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Audiences

Email & Phone Hasher

SHA-256 hash CSV files for Meta Custom Audiences and Google Customer Match

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Email & Phone Hasher

CSV → SHA-256 hashed CSV (Meta / Google / TikTok compatible). 100% browser, no upload.
or drop CSV file here

What to do with this file

You've got a SHA-256 hashed CSV. Here's how to upload it as a Custom Audience.

FB Meta Ads (Facebook & Instagram)
  1. Open Business Manager → Audiences
  2. Click Create Audience → Custom Audience → Customer List
  3. Choose "Use my own data and prepare/hash it myself" — important: skip Meta's auto-hash since the file is already hashed
  4. Upload your hashed_*.csv file. Map columns: email_sha256 → Email (SHA256), phone_sha256 → Phone (SHA256)
  5. Name the audience and click Upload & Create. Match rate appears in 30-60 min
💡 Healthy match rate: 50-70% for fresh CRM lists, 30-50% for 6+ months old
G Google Ads (Customer Match)
  1. Open Tools & Settings → Shared Library → Audience Manager → Customer Lists
  2. Click + button → Upload a customer list
  3. Check "Data in this file is hashed"
  4. Upload the hashed_*.csv. Google expects column headers like Email, Phone — rename them in the CSV before upload
  5. Set membership duration (default 540 days) → click Upload and create
💡 Minimum 1000 matched users required before Google lets you target the audience
TT TikTok Ads
  1. Open Assets → Audiences → Create Audience → Customer File
  2. Select "Pre-hashed (SHA256)" option
  3. Upload the file, map email_sha256 → Email, phone_sha256 → Phone
  4. Wait 1-3 hours for matching. Use as is, or build Lookalike off it
💡 TikTok match rates are typically 15-30% lower than Meta

Tips for better match rates

  • Include both email AND phone when possible — Meta matches on either, doubling your chance
  • Don't include test/example emails (john@example.com, etc.) — they reduce overall match quality
  • Refresh the audience every 30-90 days as your CRM grows
  • Never share your raw CSV — only the hashed version is safe to upload

Upload a CSV with emails and phones. Get back a properly hashed file (SHA-256, lowercase, trimmed, E.164 phone format) ready to upload as Custom Audience on Meta, Google, TikTok, or LinkedIn.

Why this exists

Ad platforms require user PII to be hashed before upload (privacy compliance). Most teams hash manually in spreadsheets — slow, error-prone, often skips normalization steps that cause low match rates.

Use cases

  • Upload CRM customer list as Meta Custom Audience
  • Create high-value lookalikes from top-AOV buyer segment
  • Sync purchaser data across Meta, Google, TikTok
  • Build suppression audiences (existing customers to exclude)

FAQ

Where does my data go?
Nowhere. Hashing happens 100% in the browser via Web Crypto API. The CSV never leaves your device.
Does it normalize phones?
Yes. Auto-detects country code, strips formatting, converts to E.164 (+15551234567).
How big a file can I process?
Tested up to 500,000 rows. Processing time scales linearly (~10 sec per 100k rows).