How to Calculate Bond Duration

What is Bond Duration?

Bond duration measures price sensitivity to interest rate changes. Macaulay duration is the weighted average time to cash flows; modified duration estimates price change per 1% rate move.

Formula

Macaulay Duration = Σ[t×PV(CFₜ)] / Bond Price | Modified Duration = D/(1+y)

D: Macaulay duration (Years)
y: Yield to maturity (Annual %)
CF_t: Cash flow at time t (Currency)

Step-by-Step Guide

1Macaulay duration = Sum[t x PV(CF_t)] / Bond price
2Modified duration = Macaulay / (1 + YTM)
3Price change approx -Modified Duration x dYTM x Price

Worked Examples

Input

$1,000 bond, 5% coupon, 6% YTM, 5 years

Result

Macaulay approx 4.49 years, Modified approx 4.24

Frequently Asked Questions

What is Bond Duration Calc?

Bond duration measures price sensitivity to interest rate changes. Macaulay duration is the weighted average time to cash flows; modified duration estimates price change per 1% rate move

How accurate is the Bond Duration Calc calculator?

The calculator uses the standard published formula for bond duration calc. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.

What units does the Bond Duration Calc calculator use?

This calculator works with inches, percentages. You can enter values in the units shown — the calculator handles all conversions internally.

What formula does the Bond Duration Calc calculator use?

The core formula is: Macaulay duration = Sum[t x PV(CF_t)] / Bond price. Each step in the calculation is shown so you can verify the result manually.

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