Google Sheets Phone & Email Validation
Validate phone numbers and verify emails in place with a simple custom function, clean a whole sheet without exporting to another tool.
The 1Lookup Google Sheets integration validates phone numbers and verifies emails directly in a spreadsheet using a custom Apps Script function. Type a formula like =LOOKUP_PHONE(A2) next to your data and each row returns its validity, line type, carrier, or email deliverability, letting you clean an entire list in place without exporting it.
Why validate spreadsheets with 1Lookup
Spreadsheets are where most lead lists and contact exports start their life, and where bad data hides. 1Lookup lets you validate phone numbers and emails right in Google Sheets, so you can clean a list before it ever reaches your CRM, dialer, or email tool.
A small Google Apps Script wraps the 1Lookup API as a custom spreadsheet function. Once it is added, validating a column is as simple as dragging a formula down the rows. Each cell returns the verdict and any fields you choose, line type and carrier for phones, deliverability for emails, so the whole sheet becomes a live, validated dataset.
What you can do
Custom function (=LOOKUP_PHONE / =LOOKUP_EMAIL)
Call 1Lookup like any other spreadsheet formula and fill results down a column in seconds.
Validate in place
Clean lists inside the sheet, no exporting to a separate validation tool and re-importing.
Bulk-friendly
Validate hundreds of rows by dragging the formula; combine with batch endpoints for larger files.
Collaborative
Because it lives in the sheet, anyone with edit access can validate data without extra software.
How to validate phone numbers and emails in Google Sheets
Create a 1Lookup account and API key
Sign up for 1Lookup and generate an API key. Free-tier lookups let you test the function before validating a full list.
Open Apps Script
In your Google Sheet, open Extensions → Apps Script to create a bound script project.
Add a custom function
Paste a small function that calls the 1Lookup API with UrlFetchApp and returns the field you want, then save and authorise it. Store the API key in Script Properties rather than in the code.
Use it like a formula
In a cell next to your data, enter =LOOKUP_PHONE(A2) (or =LOOKUP_EMAIL(B2)) and drag it down to validate the whole column.
Use cases
Clean a lead list before import
Validate an exported list in Sheets and remove invalid rows before pushing it into your CRM or dialer.
Ad-hoc checks for non-technical teams
Let ops, sales, or marketing validate a column of numbers or emails without learning an API.
Frequently asked questions
Is the Google Sheets integration an add-on or a script?
It is a lightweight Google Apps Script bound to your sheet that exposes 1Lookup as a custom function. You paste a short script once, authorise it, and then use it like any built-in formula.
Where do I store the API key?
Store it in Apps Script's Script Properties rather than hard-coding it in the function, so the key is not visible to everyone with access to the sheet.
How many rows can I validate?
You can drag the formula down hundreds of rows for everyday lists. For very large files, use 1Lookup's batch validation rather than a per-cell function to stay within spreadsheet and rate limits.