Sales & MarketingGoogle Workspace

Prepare a Google Ads Customer Match List in Sheets

8apps Team·

The upload succeeds either way – the match rate is what fails. Here's the Sheets-to-Customer-Match workflow with Google's own formatting rules at each step.

The API tells you the stakes

Google's own developer documentation says it plainly: "If the contact information is not correctly formatted before hashing, the API still accepts the hashed information, but it can't be matched with a customer." No error, no warning – just a list that silently matches nobody. So the workflow below is mostly formatting, and the hash is one step near the end.

Step 1 – one identifier per column, plain text first

Lay the sheet out with each identifier in its own column – email, phone, name fields, country and postal code as applicable – and set phone and postal columns to plain text before pasting (Format → Number → Plain text), or leading zeros and long numbers are silently destroyed on arrival.

Step 2 – normalise to Google's documented rules

For hashed fields, Google's file-format documentation is specific:

  • Lowercase everything, strip surrounding whitespace.
  • Email, Gmail-only rule: for gmail.com and googlemail.com addresses, remove periods in the username and anything from a + onwards – Jane.Doe+Shopping@googlemail.com becomes janedoe@googlemail.com. Documented for those two domains only; do not apply it to other domains.
  • Phone: E.164 – "Include the country code and '+' sign." The full formatting pass is our E.164 guide; the short version is digits only, country code, leading +.

Step 3 – hash, or let Google hash

Two documented paths:

  • Upload plaintext and Google hashes the data on its side before matching.
  • Hash yourself – SHA-256, hex output (Google's wording: "Use hex SHA256") – so raw customer data never leaves your sheet in readable form. This is the route compliance-minded teams take, and the reason this workflow exists in Sheets at all: Sheets has no built-in hash function, so the hashing step needs Apps Script or an add-on.

Step 4 – verify before uploading

Two ten-second checks that catch most silent failures:

  • Length check: a SHA-256 hex digest is exactly 64 characters – =LEN(B2)=64 flags truncation and double-hashing at once.
  • Spot check: hash one value whose input you normalised by hand and confirm the digest changes when the input casing changes. If John@ and john@ give the same digest, something upstream is pre-processing your data.

Step 5 – upload and set expectations

Upload the file to your customer list in Google Ads. Processing is not instant, and the matched size will be smaller than your row count – matching happens against signed-in Google accounts, and no formatting discipline changes that. What formatting discipline changes is whether a matchable row actually matches. If the rate looks wrong, our match-rate troubleshooting guide walks the causes in diagnostic order.

Where Hash Data fits

Hash Data puts the hashing step inside the sheet: several algorithms as formulas, and =HASHPHONE() normalising a number to E.164 and hashing it in one step – the two most error-prone steps above, collapsed into one.

→ Hash Data on the Google Workspace Marketplace

Sources

Tags

google adscustomer matchgoogle sheetssha256hash dataaudience uploadpii8apps
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