Engineering Calculations on-line
The web is loaded with on-line calculators. For example
What we need is a very convenient index, or search function that works great, so we have reliable quick access to a calculator for just what we want to calculate, every time. Well, we don't have that, so let's go computer-whizzes! Make it happen.
In the meantime, here's what I've found.
Martindale's has the best index I've found so far to on-line engineering calculators. When you get to their page, go look for the Engineering section.
EEVL, or whatever, might be your next try. Do a search for "calculations on-line" or "calculations (your subject)" and you'll get a lot of hits, but not necessarily everything is really an on-line calculator.