Find the nearest zip code with Microsoft Excel

Microsoft Excel’s “custom functions” can perform many specialized tasks related to address and location-based information, such as checking the validity of postal addresses, importing demographic information, and even calculating driving time and driving distance. Custom functions, also called UDFs (User Defined Functions) perform complex calculations or tasks and are used in cell formulas just like the standard Excel functions SUM or AVERAGE. In this article we will describe how to use custom functions to identify which ZIP code within a list is closest to a destination location.

Identifying the nearest zip code or address has many applications. For example, a potential customer mailing list can match the closest store locations, or a list of delivery addresses can be mapped to the closest distribution centers. This type of analysis requires geocoding coordinates (latitude and longitude) to calculate the straight-line “straight-line” distance between locations. After completing these distance calculations for all possible ZIP code combinations, the one with the shortest distance is selected.

How can this be achieved within an Excel spreadsheet? A custom function can automatically capture latitude and longitude data from a local database and then perform distance calculations based on this data. Since all of this happens completely in the background, there is no need to learn a new application or even leave the familiar environment of Excel. For example, let’s say we have a list of store addresses in worksheet range A1 to A10. We can find the store closest to a customer in zip code 08034 by entering the custom function in a worksheet cell like this: “= CustomFunction (A1: A10, 08034)”. The result returned to the worksheet will be the closest store within the specified range A1: A10.

We can apply the same custom function to multiple customer addresses listed in column B. If the customer’s first ZIP code is in cell B1 of the worksheet, the formula in cell C1 would be = Custom Function (A1: A10, B1). Then we can simply copy and paste this formula into the rest of the list to find the closest store for each customer.

This is a good example of how Excel custom functions can automate various tasks and calculations, without the need to learn a new application or even leave the familiar Excel environment. From verifying the validity of address information to finding the closest ZIP code to a destination location, custom functions can be valuable tools for analyzing address and location-based information.