Google Sheets phone and email validation

A custom LOOKUPLAB() function in Apps Script to validate a whole column.

Why validate inside Google Sheets

Most lead lists start life as a spreadsheet. A custom function in Apps Script lets anyone validate a column by dragging a formula down, no engineering required. Results cache in the sheet so you only pay once per row.

Paste the script below into Extensions > Apps Script, add your key, and use =LOOKUPLAB_PHONE(A2) or =LOOKUPLAB_EMAIL(B2).

Setup

Open Extensions > Apps Script in the sheet.
Paste the function: function LOOKUPLAB_PHONE(n){var r=UrlFetchApp.fetch('https://lookuplab.io/api/v1/phone/?number='+encodeURIComponent(n),{headers:{Authorization:'Bearer YOUR_API_KEY'}});var d=JSON.parse(r.getContentText()).data;return [[d.valid,d.line_type,d.carrier]];}
Use =LOOKUPLAB_PHONE(A2) in a cell and drag down. Three columns fill in: valid, line type, carrier.
Copy and paste values once done so the sheet does not refetch on every recalculation.

What teams build with it

Clean a purchased list before it goes to the dialer.
Score webinar registrants.
Validate before importing into a CRM.

Get a key and connect Google Sheets

One API key, one credit pool, 1,000 free lookups to start. Phone, email, IP and DNS checks from a single endpoint, and you only pay for lookups that return an answer.

Start free Read the docs

Questions

Will it recalculate and charge me again?

Custom functions can refetch on edit. Paste as values when you are done. Our seven-day cache also means a repeated lookup of the same number is not charged upstream.

Related: Airtable