Discounted Payback Period Calculator
Estimate the first recovery of a positive initial investment from discounted signed future cash flows.
Enter only CF1 onward at equally spaced period ends. The initial investment occurs at time zero. Use one currency and a discount rate matching the period unit. Recovery is the first cumulative discounted crossing; later losses do not undo this first-recovery result. Fractional periods assume linear recovery within the crossing period.
Manual inputs stay in this browser. No external data is fetched. This is a mathematical estimate, not investment advice.
References: LibreTexts · 9.3
A QUICK WALKTHROUGH
How to use this tool
- Cash flows (comma or newline separated; use a dot for decimals)
- Enter only CF1 onward at equally spaced period ends. The initial investment occurs at time zero. Use one currency and a discount rate matching the period unit. Recovery is the first cumulative discounted crossing; later losses do not undo this first-recovery result. Fractional periods assume linear recovery within the crossing period.
- Calculate
Formula
Dt = CFt / (1+r)^t; C0 = −I; Ct = Ct−1 + Dt. When Ct first reaches 0 or more, estimated recovery = (t−1) + (−Ct−1)/Dt.
Assumptions and limits
Enter only CF1 onward at equally spaced period ends. The initial investment occurs at time zero. Use one currency and a discount rate matching the period unit. Recovery is the first cumulative discounted crossing; later losses do not undo this first-recovery result. Fractional periods assume linear recovery within the crossing period.
Manual inputs stay in this browser. No external data is fetched. This is a mathematical estimate, not investment advice.
Manual inputs stay in this browser. No external data is fetched. This is a mathematical estimate, not investment advice.
GOOD TO KNOW
Common questions
What does discounted payback measure?
It estimates when cumulative discounted future cash flows first recover the positive initial investment.
Does it include cash flows after the first recovery?
No. The result is the first recovery point; later gains or losses do not change that point.