If you have been following my blog for any length of time, you know I am an enthusiastic Twitter user. I have previously written about why, so I won’t repeat myself here. Suffice it to say that I believe Twitter offers an unparalleled opportunity for brand-building, social networking, and customer engagement.

But at what cost? you may be thinking.

Obviously, the service itself is free. I don’t know how much longer the folks at Twitter can sustain this business model. Eventually, they will have to monetize it or the service will go away. But in the meantime, it costs you or your business nothing.

The learning curve itself is also inexpensive. You can get get the hang of it in less than 30 minutes. In fact, I wrote The Beginner’s Guide to Twitter as a 20-minute introduction, because I got tired of repeating the basics to new users.

But what about the time it takes to Twitter? Ah, yes, “the time.”

This is the standard objection from people who haven’t actually tried the service. “How do you find the time to Twitter?” they ask. In my experience, it takes me less than 30 minutes a day.

Here’s how the math works out. I am a pretty active Twitterer. I average about 13 tweets a day. Most tweets take me 15–30 seconds each. (Yes, I have timed them.) Don’t forget, you only have 140 characters. It can’t take much time. Nevertheless, let’s be conservative and assume that it takes me 30 seconds for each tweet.

Thirteen times 30 is 6.5 minutes. I probably spend another 15 minutes a day scanning other people’s tweets and responding to direct messages or replies. Even then, I am doing this during “down time”—early in the morning as I am reading, in between meetings or projects during the day, or in the evening as a way of relaxing. All total, that’s just over 20 minutes.

In my opinion, that’s not a big investment of time, especially for the benefits I receive. But that’s the subject of another post.