Month Over Month Growth Calculator
Month-over-month growth, what it compounds to over a year, and how it compares against the same month last year.
Month-over-month growth is (current − previous) ÷ previous.
How the month over month growth calculator works
Month-over-month growth is (current − previous) ÷ previous. Its power is compounding: a steady 5% a month is 80% over a year, and 10% a month is 214%.
The trap is seasonality. A single month-over-month figure can be entirely seasonal, which is why the year-over-year comparison is shown alongside — it removes the season by comparing like with like.
Formula: MoM = (current − previous) / previous; annualised = (1 + MoM)¹² − 1
Worked examples
| Inputs | Month-over-month growth | Note |
|---|---|---|
| 40,000 to 42,000 | 5% | 5% MoM — 79.6% annualised |
| A decline | -5% | negative growth |
| Flat | 0% | 0% |
FAQFrequently asked questions
How do I calculate month-over-month growth?
Subtract last month from this month and divide by last month.
Why annualise it?
To see what it compounds to. A 5% monthly rate sounds modest and is nearly 80% a year.
Is month-over-month or year-over-year better?
Year-over-year removes seasonality; month-over-month catches recent inflections. Most businesses watch both, and this page shows both.
What is a good monthly growth rate?
For an early-stage business, 5 to 10% a month is often cited as strong. Sustaining it for long is rare — the compounding gets implausible fast.
Why does my growth rate fall as I grow?
Because the base grows. The same absolute increase is a smaller percentage of a larger number — that is arithmetic, not decline.
Where these figures come from
- CFA Institute — Quantitative Methods: The Time Value of Money — the discounting, annuity and IRR conventions used here
- US Federal Reserve — Regulation Z (Truth in Lending), APR calculation — why APR includes fees where a nominal rate does not
- MoneyHelper (UK Government-backed) — the UK's free money guidance service
Last checked: September 2026. These are the standard textbook formulas; the conventions named are those of the CFA Institute curriculum and ISO 80000 usage.