Gathering list of postcodes within a radius ( Australia )

Hi,
i would like to find a solution to get a list of postcodes within x km from a post code input number.

Example, me inputting post code 3000 - Melbourne CBD will give me a list of post codes within lets say 5 km from 3000

Rather lacking in detail! See yellow banner at top the page on how to post a sample workbook.

I'm not sure if I am missing something, but I don't see anywhere where you have a database of distances between the different post codes, nor any explanation of how one would calculate the distance between two post codes. Did I just miss it?

Without going into programming details, yet, I would expect to solve a problem like this by:

1) Choose postcode and radius.
2) Calculate/lookup distance between chosen post code and all other postcodes of interest. Using the setup you currently have, this could be a formula in E adjacent to your list of potential results.
3) Filter/extract those postcodes where distance is less than radius. Using the current setup, I would be tempted to simply setup an autofilter using columns D and E. Once postcode is chosen in D2, filter the list using column E where E is less than the desired radius.

The key unknown right now is how to calculate distance between postcodes. Do you have a formula or database that can be used for this purpose?

Try this. I think the calculations are pretty close. I used a data base from the internet and downloaded it. The original database had sub post codes. ie there were post codes with the same suburbs but they had different long and lat coordinates which makes me think they were from a GIS database with sub post code regions. For simplicity I stripped this back to one post code. The distance is measured from thecentroid of the starting postcode to the centroid of all other postcodes and I had to use a macro to bring back the ones within the set radius (just press the button)

It?s not perfect due to me slimming down many of the duplicate post codes and you need to understand some postcodes are enormous so you need to enter a large radius to get adjoins or nearby ones captured. You?ll be able to find other post code databases I assume so feel free to copy them over the respective columns in sheet 2 to improve on this.