# Demystifying the Internal Rate of Return

As an angel, you’ve probably heard of the Internal Rate of Return (IRR) as a key metric for evaluating the potential profitability of your startup. But what exactly is IRR, and how can it help you make better business decisions? In this blog post, we’re going to demystify IRR and show you how it can be used to measure the success of your startup.

**First things first: What is IRR?**

IRR is a financial metric that measures the profitability of an investment. It calculates the rate at which the present value of all cash inflows equals the present value of all cash outflows. In simpler terms, IRR is the rate at which your initial investment will grow over time, taking into account the time value of money.

For example, let’s say you invested $100 in a startup and received a total of $150 in cash flow over three years. Assuming no other cash flows or investments, the IRR would be the rate at which $100 grows to $150 over three years.

**IRR: The Swiss Army Knife of Metrics**

One of the biggest advantages of IRR is its versatility. It can be used to evaluate the profitability of almost any investment, including stocks, bonds, real estate, and of course, startups. IRR is often used by venture capitalists to evaluate the potential of new investment opportunities. It’s also commonly used by startups to evaluate the return on investment of their various projects and initiatives.

IRR is a metric that can be used to measure the success of a startup over time. If the IRR is higher than the cost of capital, then the startup is generating a positive return on investment. If the IRR is lower than the cost of capital, then the startup is generating a negative return on investment.

**IRR: The Pitfalls and Limitations**

While IRR is a powerful metric, it’s not without its pitfalls and limitations. One of the biggest limitations of IRR is that it assumes that all cash flows are reinvested at the same rate as the initial investment. This is rarely the case in reality, especially for startups, which often have unpredictable cash flows and require ongoing investments to maintain growth.

Another limitation of IRR is that it doesn’t take into account the size of the investment. This can be a problem for startups, which often require significant upfront investments to get off the ground. A large upfront investment can skew the IRR, making it look more or less profitable than it actually is.

Finally, IRR can be misleading when used to compare investments with different cash flow patterns. For example, two investments with the same IRR may have vastly different cash flow patterns, with one investment generating a steady stream of income over time and the other generating a large lump sum at the end of the investment period.