With quantity discounts on components, sometimes it's cheaper to buy a larger quantity than you need for a particular project and save them for future use. This is a simple Windows application written in Visual Basic 6 to help you compare quantity prices so you can decide if ordering enough to get a higher price break makes sense.
This program should run under any version of Windows without installation. VBRun600.dll may need to be downloaded if it's not already installed on your computer.
Using this calculator is really simple. Enter the quantities and unit cost or extended cost for the range bracketing your needed quantity. In the illustration to right, I need six parts, so I've entered the break breaks for 1 and 10 quantities. The program calculates the crossover point as 8 parts - if I buy 8 parts, it's cheaper at the Qty 1 part. If I'm buying more than 8, I might as well buy 10 and get one free.
The fourth row calculates the lot price based on the smaller quantity price.
Using the calculator allows you to quickly evaluate alternative prices, to help build up your parts collection.
In the example shown above, I need 20 of the TMP512 chips. I entered the price breaks for 10 and 25 quantities. The calculator shows that 22 is the crossover point. If I opt to buy 25, I'll get 5 extra chips for about $2 a piece.
The program doesn't have much in the way of fancy formatting but it does include some error checking to keep you out of trouble. You can tab from one field to the next or use the mouse to select which field to enter.
Let me know if there are any additions that may be useful or if you have any problems using the program.