Google Sheets phone and email validation

Why validate inside Google Sheets

The downloadable Apps Script adds a LookupLab menu to your spreadsheet. Select up to 100 rows, run a check, and save validity, line type, carrier, country and credits charged beside the original number.

The script skips previously checked rows and writes each result immediately. It stops on an HTTP error instead of quietly labeling a service failure as a bad phone number. Use a dedicated sheet because columns B:H are reserved for results.

Setup

1. Make a dedicated sheet with phone in A1. Format column A as Plain text before pasting E.164 numbers. Leave columns B:H empty.
2. Download the Apps Script below and paste it into Extensions > Apps Script. In Project Settings > Script Properties add LOOKUPLAB_API_KEY with your key. Sheet/script editors can access this key; share accordingly.
3. Save and reload the sheet. Select up to 100 rows below the header, then choose LookupLab > Check selected phones. Approve Google authorization for the script.
4. Review the saved values in B:H. Only changed or intentionally rechecked rows should run again. To recheck a row, clear its existing B:H results first.
5. Keep a copy before merging results into a CRM. A carrier match does not prove ownership or contact permission.

Walk through the complete workflow.
See the setup, sample output and review rules →

Phone validation is not consent, ownership verification or guaranteed delivery. Email syntax and MX checks establish domain-level signals, not proof that a particular mailbox exists.

What teams build with it

• Enrich a small phone list before CRM import.
• Separate landline and mobile records for channel review.
• Audit the credit cost of a sample before checking a full list.

Related: Airtable