Direct Answer
Discounted cash flow (DCF) is a valuation method that estimates a company's intrinsic value by projecting its future free cash flows over a forecast period, then discounting those cash flows - plus a terminal value covering everything beyond the forecast - back to present value using a discount rate that reflects the riskiness of those cash flows, commonly the weighted average cost of capital (WACC). Because the result is highly sensitive to the growth, margin, and discount-rate assumptions used, DCF output is best treated as a range across scenarios rather than a single precise number.
Key Takeaways
- DCF estimates intrinsic value by projecting free cash flow over a forecast period and discounting it, along with a terminal value, back to the present.
- The discount rate reflects the riskiness of the projected cash flows - commonly the weighted average cost of capital (WACC) for a whole-company valuation.
- Terminal value covers everything beyond the explicit forecast period and often makes up a large share of the total estimated value.
- Small changes in growth, margin, or discount-rate assumptions can produce large swings in the resulting value - this is a defining characteristic of the model, not an edge case.
- Because of that sensitivity, a DCF output is best treated as a range under different scenarios rather than a single precise number.
- DCF is one of several valuation approaches; it works best alongside comparable-multiples and other methods, not in isolation.
What Is Discounted Cash Flow (DCF)?
Discounted cash flow is a valuation method that estimates a company's intrinsic value by projecting its future free cash flows over a forecast period, then discounting those projected cash flows - plus a terminal value - back to present value using a discount rate that reflects the riskiness of those cash flows. The underlying idea is that a business is worth the cash it can generate for its capital providers over time, adjusted for the fact that a dollar received later is worth less today than a dollar in hand now.
That adjustment is what "discounting" means: each future cash flow is reduced by a factor based on how far out it occurs and how risky it is judged to be. The discount rate most commonly used for a whole-company DCF is the weighted average cost of capital (WACC), a blended rate reflecting the return required by both the company's debt holders and equity holders. A DCF is one of several valuation approaches used alongside comparable multiples, reverse DCF, and other methods described in the broader valuation models guide - it is not treated as a standalone verdict on a stock's price.
The DCF Formula and Mechanics
A DCF has three moving parts: a forecast of free cash flow over an explicit period, a terminal value covering everything beyond that period, and a discount rate applied to both.
| Component | What it represents |
|---|---|
| Forecast-period free cash flow | Projected cash the business generates in each year of the explicit forecast, usually several years out. |
| Terminal value | An estimate of the value of all cash flows occurring after the forecast period ends, discounted back alongside the forecasted years. |
| Discount rate | The rate used to convert future cash flows into present value, reflecting the riskiness of those cash flows - commonly the weighted average cost of capital (WACC). |
| Present value | The sum of each discounted forecast-period cash flow plus the discounted terminal value - the model's resulting intrinsic-value estimate. |
Mechanically, each year's projected free cash flow is divided by (1 + discount rate) raised to the power of how many years out that cash flow occurs, which shrinks cash flows further in the future more than cash flows arriving sooner. The terminal value is calculated as of the end of the forecast period and then discounted back to today using that same compounding approach. Summing every discounted forecast-year cash flow with the discounted terminal value produces the model's estimate of intrinsic value.
Because the discount rate compounds over multiple years and the terminal value typically represents a large share of the total, the model is inherently sensitive to the growth rate, margin assumptions, and discount rate chosen - a theme carried through the rest of this page.
DCF Valuation Calculator
Enter a base year-1 free cash flow, an annual growth rate, a forecast length, a discount rate, and a terminal growth rate to compute an intrinsic value estimate using the same mechanics described above: each forecast year's free cash flow discounted at (1 + discount rate) raised to that year, plus a Gordon Growth terminal value discounted back at the same rate.
Worked Example
Hypothetical example - for education only. Assume a company is projected to generate the following free cash flow over a five-year forecast period, and an analyst applies a 9% discount rate to reflect the estimated riskiness of those cash flows:
| Year | Projected free cash flow | Discount factor (1.09^n) | Present value |
|---|---|---|---|
| Year 1 | $100.0M | 1.090 | $91.7M |
| Year 2 | $107.0M | 1.188 | $90.1M |
| Year 3 | $114.5M | 1.295 | $88.4M |
| Year 4 | $122.5M | 1.412 | $86.8M |
| Year 5 | $131.1M | 1.539 | $85.2M |
Summing the five discounted cash flows gives approximately $442.2M in present value from the explicit forecast period. Suppose the analyst then estimates a terminal value of $2,400M as of the end of Year 5 (reflecting cash flows expected beyond the forecast period), and discounts that terminal value back five years at the same 9% rate: $2,400M ÷ 1.539 ≈ $1,559.8M in present value.
Adding the two pieces together - $442.2M from the forecast period plus $1,559.8M from the discounted terminal value - produces an estimated intrinsic value of approximately $2,002M. Note that in this illustration, the terminal value contributes roughly 78% of the total estimate, which is a common pattern in DCF models and one reason the terminal-value assumptions deserve as much scrutiny as the forecast-period assumptions.
- This example is hypothetical and simplified - taxes, share count, net debt, and other adjustments needed to move from enterprise value to a per-share figure are omitted.
- A different growth rate, margin assumption, or discount rate applied to the same starting cash flow would change the result meaningfully - that sensitivity is discussed further below.
- Actual results can differ materially from any projection, since future cash flows depend on business performance and conditions that cannot be known in advance.
How DCF Is Used and Interpreted
A DCF output is generally treated as an estimate of intrinsic value that can be compared against a company's current market price or against other valuation approaches, not as a guaranteed fair-value figure. Because the model is highly sensitive to its inputs, a single DCF run built on one set of assumptions carries limited weight on its own.
A more careful use of the model builds several scenarios - commonly a base case alongside more conservative and more optimistic cases for growth, margins, and the discount rate - and reports the resulting range rather than a lone number. Sensitivity analysis, which shows how the estimated value changes as one or two key inputs (such as the discount rate and the long-run growth rate) are varied across a plausible range, is a standard way to visualize how much the conclusion depends on assumptions rather than on the underlying business fundamentals.
DCF is also commonly used alongside comparable-multiples analysis and other approaches described in the valuation models guide, since methods that rely on different inputs and assumptions can help identify whether a DCF's result is an outlier or is broadly consistent with how the market is pricing similar businesses.
Limitations and Common Mistakes
| Mistake | Why it causes problems | Better practice |
|---|---|---|
| Treating the output as a single precise number | Small changes in growth, margin, or discount-rate assumptions can produce large swings in the result, so a single figure implies false precision. | Present a range built from base, conservative, and optimistic scenarios rather than one point estimate. |
| Extending high near-term growth too far | Projecting an early growth rate across the entire forecast period, rather than tapering it, can overstate the forecast-period cash flow and the resulting value. | Taper growth assumptions toward a more sustainable long-run rate as the forecast period progresses. |
| Under-scrutinizing the terminal value | Terminal value frequently represents a large share of total estimated value, so a small change in its assumptions can swing the whole result more than any single forecast year. | Give the terminal-value assumptions (long-run growth rate or exit multiple) the same scrutiny as the forecast-period numbers. |
| Picking a discount rate that doesn't reflect real risk | Using a discount rate too low for the business's actual risk profile inflates the present value of every projected cash flow. | Base the discount rate on the estimated riskiness of the cash flows - commonly the weighted average cost of capital (WACC) - rather than a generic or borrowed figure. |
| Skipping sensitivity analysis | Without testing how the result changes as inputs vary. It is easy to mistake a fragile, assumption-driven number for a robust conclusion. | Vary the discount rate and growth assumptions across a plausible range and report how much the value estimate moves. |
The broader limitation is that DCF depends entirely on projecting the future, and no projection can be known with certainty - a well-built model can organize assumptions clearly, but it cannot remove the underlying uncertainty about how a business and the economy will actually perform. DCF outputs should be treated as one input into a broader analysis, not as a definitive statement of what a company is worth.
Frequently Asked Questions
What discount rate should a DCF use?
The discount rate should reflect the riskiness of the projected cash flows - commonly the weighted average cost of capital (WACC) when valuing the whole company. A higher-risk business with less certain cash flows generally calls for a higher discount rate, which lowers the present value of the same projected cash flows.
Why is DCF output described as a range instead of one number?
DCF is highly sensitive to the assumptions used for growth rates, margins, and the discount rate, and small changes in those inputs can produce large swings in the resulting value. Treating the output as a single precise number overstates the model's precision - a range across different scenarios better reflects the underlying uncertainty.
What is terminal value in a DCF, and why does it matter so much?
Terminal value estimates the worth of all cash flows beyond the explicit forecast period, discounted back to present value alongside the forecasted years. Because it often represents a large share of total estimated value, the assumptions behind it - particularly the long-run growth rate or exit multiple - deserve as much scrutiny as the forecast period itself.
Does a DCF work for every company?
DCF is generally more workable for companies with visible, projectable free cash flow. Businesses with volatile, negative, or highly unpredictable cash flow make the projection step far less reliable, which is one reason DCF outputs are best treated as a scenario range rather than a single precise figure.
How is free cash flow different from net income in a DCF?
Free cash flow reflects cash actually generated by the business after operating expenses and capital investment, while net income includes non-cash accounting items such as depreciation. A DCF discounts projected free cash flow because that is the cash available to the company's capital providers, not an accounting profit figure.
How long should the explicit forecast period be?
Long enough for the business to reach a steady state where the terminal assumption is reasonable, which for a mature company may be five years and for a fast-growing one considerably longer. Terminating the explicit period while growth is still elevated forces the terminal value to absorb assumptions it handles poorly. The length should follow from when the business stabilises rather than from convention.
Which free cash flow definition should the model use?
Cash flow to the firm, before interest and after tax on operating profit, pairs with the weighted discount rate and produces enterprise value. Cash flow to equity, after interest and debt movements, pairs with the cost of equity and produces equity value directly. Both are valid and mixing the definitions with the wrong rate is the most common structural error in these models.
How should working capital be forecast within the model?
As a function of revenue based on the historical relationship, since working capital scales with activity for most businesses. Forecasting it as a fixed amount, or omitting it, understates the cash growth consumes. For a rapidly growing business this omission can be large enough to change the conclusion.
What check confirms a model's assumptions are internally consistent?
The implied return on incremental capital should be plausible: if the model forecasts substantial growth with little reinvestment, it is assuming returns no business sustains. Computing the implied reinvestment rate and the implied return on it is a straightforward check most models fail. It catches optimism that is invisible in the individual line items.