Here's a clever calculator that let's you answer the age-old question: "is this thing worth automating?"

I put this together a few days ago and I just keep needing to use it! Situations keep coming up where I'm gobsmacked to find that our 'gut-feel' about the relative merits of two approaches is just not borne out by the simplest back-of-the-napkin calculation.

The neat thing about this calculator is that it distills the choice down to its most crucial elements, so you can come up with an answer very quickly.

Once you've plugged in some values and gotten your answer, you can easily share it with those chumps in management or with a clever colleague -- click the 'Save this result' button, and you'll be given a url that you can send around, preserving all the values you plugged in, allowing others to tinker with your calculation and verify everything for themselves. (Implementing that bit was the funnest of the fun. Remind me to show you the 'GetHashyCode' extension method.)

When you take a moment to play with the figures, there's a bunch of things that leap out at you.

First up -- this rather obvious result:

"If you're only going to do it once, it's not worth automating."

That might be quite a shock to some of my automation-happy friends, but I'm afraid the result is unequivocal.

Second: it's amazing how much value you can add by automating something that happens a lot.

Imagine your company has a timesheeting system that takes 10 minutes longer to complete than it should. It's used every week by 20 people, so in the next 2 years it will be filled out approximately 2000 times. You work out a way to save those 10 minutes.... how much effort should you put into making this improvement? Should you bail out if you can't fix it in 1 day? 2 days? 3 days? Here are the figures. It turns out the break even point is 430 hours of work -- around 11 weeks! So yes, if it's going to cost you a whole day of work to improve the timesheeting system -- go ahead and do it! You'd be insane not to!

Of course, the benefits of automation are more than just the time it can save. When a task becomes free to do it changes the nature of the value proposition. Read about the amazing impact of Jan Ernest Matzelinger -- a brilliant automator who revolutionised the shoe industry.

The calculator could be simpler, or it could be more complex.

A simpler version would remove the 'hourly rate' fields -- so the answer would be in just hours.

A slightly more complex version would allow there to be a different hourly rate for the person who cleans up when manual work goes wrong. This is realistic. Clean up crews can be expensive. Also the costs of maintaining the automation could be factored in. Cheap automation solutions tend to be very brittle.

Okay -- I'm all out of discussion about this little tool. Use it, share it, automate something today.