The discount rate is typically determined by calculating the firm's Weighted Average Cost of Capital, or WACC (See the WACC section to see full steps to calculate the WACC). Investors use WACC as a representation of the expected Required Rate of Return
from their investment in the company.
If you have entered your own value, the Discount Cash Flow calculation will be based off of your provided value for the discount rate.
Where:
E = Market value of the firm's Equity
D = Market value of the firm's debt
V = E + D
Re = Cost of Equity
Rd = Cost of Debt
Tc = Corporate tax rate
Where:
FCFn = Last Projected Free Cash Flow
g = Perpetual Growth Rate
r = Discount Rate