Two postcodes on databse to return distance?

I am creating a 'Mileage Calculator' in order to deduce the reimbursable miles employees drive per week. I am using Excel and have a database of all the possible 'A-B' combinations of our local postcodes (UK), and the distance in miles between each once, for example: | PL34 0ES | PL34 0AT | 0.7 |. The user, on a different sheet, selects a starting postcode and a finishing postcode for each of the journeys from a drop down list. What formula would I use to display the distance from the database as a result of the two input postcodes? Any help MUCH appreciated. Been trying to sort this all week

I am trying to do a similar thing to calculate driving time from point a to point be where both are variable. was trying to do it via VLOOKUP but would need to put every variable in 2 columns instead of the table I have. I currently have 80 locations I need to know driving time between.

I think this may be of some assistance to you Grant. http://www.doogal.co.uk/DrivingDistances.php

Here's what I would do:
In the database tab, you probably have a column for point A postcode, and a column for point B postcode, and a column for the mileage between.
Create a colum that combines column A and B - something like =A2&"-"&B2 . This will create a cell with both postcode separated by a dash (a unique reference)
In the user sheet, do the same thing to combine the two inputs into one unique reference.
Then do a vlookup on this unique reference in the database tab, to return the mileage.

Hi hardbody, posted this link and it has a copy of my spreadsheet, I don't suppose I could be really cheeky and ask you to have a look at it to help me better understand what you mean? http://www.excelforum.com/excel-gene...-database.html

Copy of Mileage calculatorsam (1).xlsxTry this - I've also linked postcodes to the start and finish columns in the calculator.

Cheers guys, that unique refrence really helps although I now have 6162 refrences I need to work out time and distance data for