DCF Sensitivity Calculator

Estimate how enterprise value changes with discount rate and terminal growth assumptions (simple 3x3 sensitivity).

Most DCFs are dominated by discount rate and terminal value assumptions. A sensitivity grid helps you see how fragile (or robust) your valuation is.

This calculator computes enterprise value at a 3x3 grid around your base discount rate and terminal growth assumptions.

Prefer an explanation- Read the guide.
 
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Tip: you can type commas (e.g., 10,000).

Example

Using the default inputs, the result is:
$92,389,745.51
Current annual free cash flow (FCF)
$5,000,000
Forecast years
5
Forecast growth (annual)
15%
Base discount rate
12%
Discount rate step
2%
Base terminal growth
3%
Terminal growth step
1%

How to calculate

  1. Enter current annual free cash flow (FCF) and a simple forecast (years + growth).
  2. Enter base discount rate and terminal growth.
  3. Enter steps for discount rate and terminal growth to generate a 3x3 grid.

Formula

EV = sum (FCF_t/(1+r)^t) + (FCF_(n+1)/(r - g_terminal))/(1+r)^n; Sensitivity varies r and g_terminal
  • Uses a simple constant growth forecast during the explicit period.
  • Terminal value uses a perpetuity growth model.
  • Only shows a small grid; use broader scenarios for full sensitivity analysis.

FAQ

Why do some grid points disappear-
Because the perpetuity model requires terminal growth to be less than the discount rate (r > g). When g is too high relative to r, the terminal value becomes mathematically invalid.
How should I pick the steps-
A common starting point is +/-1-3% for discount rate and +/-0.5-1% for terminal growth. If valuation changes wildly, you need more conservative assumptions and/or better forecasting detail.

Common mistakes

  • Terminal growth >= discount rate (invalid in perpetuity model).
  • Treating a single scenario as precise (false precision).
  • Using accounting profit instead of free cash flow.

Quick checks

  • Use consistent time units (monthly vs annual) when entering rates and cash flows.
  • Run a sensitivity check on the input that drives the result most (often discount rate or growth).
  • Treat the output as a decision aid, not a prediction; validate assumptions with reality.