Effective Duration Calculator

Estimate a bond’s price sensitivity to yield changes using prices before and after a small rate move. This page also keeps the formula, examples, FAQs, and references close by so you can check the result with confidence.

What This Effective Duration Calculator Helps You Do

Effective duration measures how much bond price changes for a small yield shift. Review the formula and examples below if you want to see how the result is derived.

This page is meant to give you a fast answer, but it also helps you double-check the math before you make a decision. Start with the inputs that you already know, run the calculation, and then compare the output with the formula, examples, and FAQs below so you can see whether the answer fits the situation you are modeling.

If the result looks off, the usual causes are a unit mismatch, a missing decimal, the wrong scenario, or a value that needs to be entered as a rate instead of a total. The notes on this page are designed to make those checks easy without forcing you to leave the calculator and search for context elsewhere.

  • Use the calculator first for a quick estimate.
  • Use the formula to understand how the result is built.
  • Use the examples to compare common use cases.
  • Use the references when the answer depends on a standard or assumption.

Common Checks

A quick result is useful, but the best result is one that still makes sense when you look at it a second time. If you are comparing scenarios, try changing one input at a time so you can see which variable has the biggest impact on the final answer. That makes it much easier to spot whether the calculation matches your expectations.

It also helps to keep the context of the problem in mind. A calculator can tell you the math, but you still need to decide whether the input represents a total, a rate, an average, or a category-specific assumption. When in doubt, start with a simple example from the page and scale up from there.

  • Check that every unit matches the rest of the problem.
  • Keep rates, totals, and averages separate.
  • Adjust one variable at a time when testing scenarios.
  • Use the smallest realistic input first, then scale upward.

Scenario Planning

This calculator is especially useful when you want a quick answer before you commit time, money, or effort. Try one baseline input set, then change a single number and compare the result so you can see how sensitive the answer is to that variable.

That makes the page useful for more than just arithmetic. It becomes a small decision aid that helps you compare options, test assumptions, and explain the final number with confidence when you need to share it with someone else.

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Result

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Quick Answer: Effective duration measures how much bond price changes for a small yield shift. Review the formula and examples below if you want to see how the result is derived.

How to Calculate Effective Duration Calculator

  1. Enter the three bond prices: Use the base price and the prices after a small yield move up and down.
  2. Enter the yield change: Use the size of the yield move that produced those prices.
  3. Read the duration: Higher duration means more price sensitivity to interest-rate changes.

Effective Duration Calculator Formula

Effective duration = (price if yield falls - price if yield rises) / (2 × base price × yield change).
Variable Meaning Unit
Base price Bond price at the starting yield $
Price if yield falls Bond price under a lower yield $
Price if yield rises Bond price under a higher yield $

Worked Examples

USA - Simple bond
  • Base price: $100
  • Price if yield falls: $103
  • Price if yield rises: $97
  • Yield change: 1%

Result: 3 years

The bond changes about 3% for each 1% change in yield.

UK - Less sensitive bond
  • Base price: £100
  • Price if yield falls: £101.50
  • Price if yield rises: £98.50
  • Yield change: 1%

Result: 1.5 years

Lower duration means lower sensitivity.

EU - Higher sensitivity
  • Base price: €100
  • Price if yield falls: €106
  • Price if yield rises: €94
  • Yield change: 1%

Result: 6 years

Longer duration indicates bigger price swings when rates move.

How to Interpret Your Results

Range Meaning Action
Low duration Bond prices react less to rate changes Consider whether you need less interest-rate risk.
Typical duration Moderate rate sensitivity Compare the bond with other holdings in the portfolio.
High duration Bond prices are highly rate-sensitive Check whether the yield compensates for the extra volatility.

Frequently Asked Questions

It is a measure of bond price sensitivity to interest-rate changes.

They show how the bond price changes when yields move up and down.

Yes, the result is typically interpreted in years.
Planning note: Effective duration is most accurate for small yield changes and plain-vanilla bonds.

References

Last reviewed: March 2026