The Scenario
You work at a real estate agency. The prospecting team compiled 300 addresses from recent inquiry forms into an Excel workbook — street, city, state, ZIP split across columns A through D in the Prospects worksheet. Before anyone commits budget to a direct mail campaign, your director wants every address validated. Bad addresses mean wasted print and a deliverability story nobody wants to tell the client.
The bad version:
- Save the worksheet as CSV, write a script to call Stannp's validation endpoint row by row, parse the JSON response for each address, map the validation result back to the right row in the workbook.
- If you do not have a script, try pasting addresses into Stannp's UI one at a time, stop at row 15 when it becomes obvious this will not finish today.
- Email a developer and ask them to build something. Wait two business days. The campaign is scheduled for next week.
Three hundred addresses and the realistic options are a script you probably cannot write, a UI flow that does not scale past 20 rows, or a developer dependency that takes longer than the campaign lead time.
The Easy Way: One Prompt in SheetXAI
SheetXAI is an AI agent inside your Excel workbook. It calls the Stannp address validation endpoint for every row and writes the result back into the worksheet directly.
For every row in my Excel mailing list, call Stannp to validate the postal address — street in column A, city in column B, state in column C, ZIP in column D — and write the validation result into column F. Flag rows where the address is not valid.
What You Get
- Column F populated for every row: either Valid, or Invalid followed by the specific issue or suggested correction Stannp returned.
- A scannable column that makes filtering to invalid rows straightforward before the campaign launches.
- The original address data in columns A through D stays untouched — the validation result is a new column, not an overwrite.
What If the Data Is Not Quite Ready
Addresses stored as a single string rather than split across columns
Parse the full address string in column A — assuming the format is street, city, state ZIP — extract the components, validate each one using the Stannp address API, and write the validation result and any suggestion into column B.
ZIP codes formatted as integers without leading zeros
Zero-pad all values in column D to 5 digits before validating, then call the Stannp validation API for each row using street from A, city from B, state from C, and the corrected ZIP from D — write the result into column E.
Two worksheets both needing validation
Validate every address in the Residential worksheet (street A, city B, state C, ZIP D) and the Commercial worksheet (same column layout) using the Stannp API and write Valid or Invalid into column E of each respective worksheet.
Full cleanup, deduplicate, validate, and flag in one pass
Trim whitespace from columns A through D of the Prospects worksheet, remove duplicate rows based on columns A and D, flag rows with any blank address field by writing Incomplete in column E, then validate all remaining rows using the Stannp API and write the validation result into column E — overwriting the Incomplete flag if the API call ran for that row.
Handling the format cleanup and the validation in a single prompt means you do not end up running the validation against data that still has the old formatting issues.
Try It
Get the 7-day free trial of SheetXAI and open any Excel workbook with a prospect or mailing list and ask it to validate addresses before committing to a Stannp campaign. For sending postcards to the validated list, see the bulk-send postcards spoke. For the hub overview, see How to Connect Stannp to Excel.