The Scenario
Your retail analytics team is evaluating fifteen potential store locations. The VP of Real Estate asked for the 15-minute drive catchment area for each site — a real isochrone polygon following road geometry, not a radius circle. She wants a single numeric area metric per site so she can compare them in the acquisition model. Your data is in an Excel workbook, addresses in column A. You need results by Friday.
The bad version:
- Read the Mapbox Isochrone API documentation, learn the endpoint requires coordinates not addresses, and realize you need to geocode first.
- Write a script to loop through addresses, geocode, call the isochrone endpoint, and extract the polygon from the GeoJSON response.
- Figure out how to express a GeoJSON polygon as a useful number in a spreadsheet cell.
The ask was for something that fits into an acquisition model, not a GeoJSON file.
The Easy Way: One Prompt in SheetXAI
SheetXAI is an AI agent that lives inside your Excel workbook. It reads the store addresses, calls Mapbox to geocode them and compute isochrone polygons, and writes both the GeoJSON and a computed area metric back into the workbook.
For each store address in column A, geocode it using Mapbox and calculate the 15-minute driving isochrone, then write the GeoJSON polygon into column B and the approximate reachable area in square kilometers into column C.
What You Get
- Column B with the GeoJSON polygon string for each store's 15-minute drive isochrone.
- Column C with reachable area in square kilometers computed from the polygon geometry.
- Any address that fails to geocode shows GEOCODE FAILED in column B.
What If the Data Is Not Quite Ready
You need both 10-minute and 20-minute isochrones for the model
Calculate 10-minute and 20-minute driving isochrones for each location in column A using Mapbox. Write the 10-minute GeoJSON into column B and the reachable area into column C. Write the 20-minute GeoJSON into column D and its area into column E.
Urban sites should use walking isochrones, suburban sites should use driving isochrones
For each address in column A, compute a driving isochrone if column B says SUBURBAN or a walking isochrone if column B says URBAN, both at 15 minutes, using Mapbox. Write the GeoJSON into column C and area in square km into column D.
The addresses have trailing notes that will confuse the geocoder
Strip any text after an em dash or double hyphen from the addresses in column A. Then geocode the cleaned addresses using Mapbox and compute 15-minute driving isochrones, writing GeoJSON into column B and area into column C.
Full pipeline: clean addresses, compute dual isochrones, rank sites, and flag top five
Clean column A addresses by removing any trailing notes after a dash. Geocode each cleaned address and compute both 10-minute and 20-minute driving isochrones using Mapbox. Write the 10-minute area into column C and the 20-minute area into column D. Add a Drive Ratio column E with the ratio of 20-minute to 10-minute area. Sort by column C descending and mark the top five rows in column F as TOP SITE.
One prompt handles address prep, dual-band isochrone computation, derived metrics, sorting, and ranking.
Try It
Get the 7-day free trial of SheetXAI and open the site evaluation workbook — paste in the candidate addresses and ask SheetXAI to compute catchment areas through Mapbox. The travel-time matrix article covers driving time comparisons between sites. The Mapbox hub lists every geographic workflow.