Convert effective annual growth to an equivalent monthly rate, reverse monthly growth to annual, and verify compounding with a value projection.

Enter an effective annual growth rate; the default period is monthly.

Annual Growth Rate to Monthly Formula

The following formula is used to calculate the monthly growth rate from the annual growth rate and the number of months.

m = (1 + (a) / (100))(1) / (n) - 1

Variables:

  • m is the monthly growth rate as a decimal; multiply by 100 for percent
  • a is the effective annual growth rate in percent
  • n is the number of periods per year: 12 for monthly

To calculate the monthly growth rate, take the annual growth rate, divide it by 100, add 1, raise the result to the power of 1 divided by the number of months, and then subtract 1.

Annual to Monthly Growth Rate Conversion Table (12-month compounding)
Annual Growth Rate (%) Equivalent Monthly Growth Rate (%)
-50-5.613
-20-1.842
-10-0.874
-5-0.427
00.000
10.083
20.165
30.247
50.407
60.487
70.565
80.643
100.797
120.949
151.171
201.531
251.877
302.210
402.844
503.437
* Rounded to 3 decimals. Monthly rate r solves (1 + A) = (1 + r)^12, where A is the annual growth rate.

What is Annual Growth Rate to Monthly?

The annual growth rate to monthly conversion is a method used to determine the equivalent monthly growth rate from a given annual growth rate. This is useful in financial planning, investment analysis, and business forecasting where growth rates are often expressed on an annual basis, but decisions need to be made on a monthly basis. The conversion helps in understanding how an annual growth rate translates into monthly increments, allowing for more granular analysis and planning.

How to Calculate Annual Growth Rate to Monthly?

The following steps outline how to calculate the monthly growth rate from the annual growth rate.


  1. First, determine the annual growth rate (a).
  2. Next, choose periods per year (n); use 12 for monthly.
  3. Next, calculate m = (1 + a/100)^(1/n) โˆ’ 1; multiply m by 100 to express the result as a percentage.
  4. Finally, calculate the monthly growth rate.
  5. After inserting the values and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

Annual Growth Rate (a) = 12%

Periods per year (n) = 12; the monthly result is approximately 0.948879%.