I found several model train calculators online, but they were to calculate scale MPH based on your input of scale, time, and distance. I wanted a calculator that would also Distance traveled using inputs of scale, time, and scale MPH - the reason I wanted this will be shown in FWIW-MED #2. The calculator is written for Windows use only.
You download the .rar file from this post and unrar to the folder of your choice. The .rar file includes the traincalcV1_1.exe program, and the source code traincalc.bas
To run the calculator, double click on traincalcV1_1.exe, and a Windows cmd window will open with the calculator running. Here is a screen shot
You choose the scale you want to work in by entering a letter from the choices presented - a lot of our scales, C for custom scale, or X to exit calculator. Caps or small letters are accepted. I selected o for ogauge, then hit Enter. Program echoes scale choice, then program displays choices for the calculation you want to do.
I chose m for scale MPH calculation, so I typed m and hit Enter. The program then asks for time in seconds, I entered 1 and hit Enter, then asked to enter distance in inches, I entered 12 and hit Enter. Program gives me answer of 32.7272....... (I haven't figured out how to program rounding in the language I used to write program).
The program now waits for any keystroke to run again, going back to asking for what scale you want to calculate in. The screenshot below shows doing several more calculations, the last one showing I used a custom scale of 10 for 1/10 scale.
For those interested, the program is written in Freebasic, and can be download for free from this site. https://www.freebasic.net/