There's nothing more frustrating than spending years in a startup only to discover that it can never grow to more than a few million dollars in revenue. 

Conducting a market and opportunity analysis will help you size the potential of your startup market, and determine whether the payoff from your new venture is worth the toil, sweat and tears, or whether you're about to do your first pivot.

Assessing the market requires legwork. Spend time reading industry-analyst reports, market-research reports and competitors' press releases to understand the trends, players, business models and key metrics. 

Related: 5 Steps for Creating a Long-Term Plan for Your Startup

Don't stop there. Get out of the building for discussions with investors and customers, too. 

Use whatever metric is most appropriate -- be it units, dollars, page views, eyeballs -- to ensure there is a large number of potential active users or customers and clear future-user growth in a market with rapid and predictable growth.

Watch the video below for more on how to calculate your market opportunity.

Related: Facing Startup Uncertainty? Try 2 Different Ways to Plan for the Future.