The Perpetuity Present Value Calculator determines the current worth of an infinite stream of fixed payments. At a 5% discount rate, a $1,000 periodic payment has a present value of $20,000 for an ordinary perpetuity or $21,000 for an immediate perpetuity. If payments grow at 2.5% inflation, the required capital doubles to $40,000.
Perpetuities in Long-Term Financial Planning
While a true perpetuity — an endless stream of payments — is largely theoretical, the concept provides a useful benchmark for valuing long-term assets like preferred stocks or stable real estate income streams. It's also applied in estimating terminal value in discounted cash flow (DCF) models, representing the value of a company's cash flows beyond the forecast period. A typical dividend yield for blue-chip stocks ranges from 2-4% in 2026, which can be compared to the implied yield of a perpetuity to assess relative value.
The Perpetuity Valuation Formulas
The calculation of a perpetuity's present value is remarkably straightforward:
Ordinary Perpetuity (first payment at end of period):
PV = Payment / Rate
Immediate Perpetuity (first payment today):
PV = Payment x (1 + Rate) / Rate
Growing Perpetuity (payments grow at rate g):
PV = Payment / (Rate - g)
Where Payment is the fixed amount received each period, Rate is the periodic discount rate (as a decimal), and g is the constant growth rate (must be less than Rate).
Worked Example: Valuing a Perpetual Income Stream
Consider an investment that pays $1,000 indefinitely at the end of each period with a 5% discount rate.
Ordinary Perpetuity PV:
PV = $1,000 / 0.05 = $20,000Immediate Perpetuity PV:
PV = $1,000 x (1 + 0.05) / 0.05 = $1,050 / 0.05 = $21,000Difference:
$21,000 - $20,000 = $1,000— exactly one extra paymentBreak-Even:
$20,000 / $1,000 = 20 paymentsto recover the investmentGrowing Perpetuity (2.5% inflation):
PV = $1,000 / (0.05 - 0.025) = $1,000 / 0.025 = $40,000
An investor would pay $20,000 today to receive $1,000 at the end of every period forever. If those payments need to grow with 2.5% inflation, the cost doubles to $40,000.
Rate Sensitivity and Terminal Value Applications
The perpetuity formula's extreme sensitivity to the discount rate makes it both powerful and dangerous in financial analysis. In DCF terminal value calculations, the perpetuity growth model assumes cash flows grow at a constant rate forever:
Terminal Value = Final Year Cash Flow x (1 + g) / (WACC - g)
Where WACC is the weighted average cost of capital and g is the perpetual growth rate (typically 2-3%). A small change in assumptions can dramatically alter valuations:
- At 5% discount / 2% growth: TV multiplier = 1/(0.05-0.02) = 33.3x
- At 5% discount / 3% growth: TV multiplier = 1/(0.05-0.03) = 50.0x
- At 4% discount / 2% growth: TV multiplier = 1/(0.04-0.02) = 50.0x
This sensitivity explains why analysts stress-test multiple discount rate and growth rate scenarios when using perpetuity-based valuations.
