Sales growth calculator

Compare sales for two matching periods. This free sales growth calculator shows the change in dollars and the percentage growth or decline, with a simple bar chart of the two totals and every step of the working. Use it for a month, a quarter, a year or one product line, as long as both periods cover the same kind of time.

How to use the sales growth calculator

1. Enter sales for the earlier period, such as last October. It must be greater than zero, because growth from zero sales has no percentage.
2. Enter sales for the current period, such as this October. Zero is allowed and shows a 100% decline.
3. Select Calculate to see the dollar change, the growth rate and a chart of the two totals. Use example loads the worked example below.

Enter both amounts on the same basis. If one figure is net sales before tax, the other should be too. Mixing gross and net sales, or sales with and without returns, changes the answer without anything having happened in the shop.

Sales growth formula

Sales change = current period sales − earlier period sales

Sales growth = sales change ÷ earlier period sales × 100

The earlier period is the denominator. A move from $48,000 to $52,800 is 10% growth because $4,800 ÷ $48,000 × 100 = 10%. Dividing by the current period would answer a different question and give a smaller number.

A negative result is a decline. If sales fall from $40,000 to $36,000, the change is −$4,000 and the growth rate is −10%. A later recovery to $40,000 is 11.11% growth, not 10%, because it starts from the smaller figure.

Worked example: October to October

A fictional shop compares October this year with October last year:

The result is sales growth of 10% between the two Octobers. Comparing the same month a year apart keeps the season the same, so a busy holiday month is not compared with a quiet one.

Compare periods fairly

Pick periods of the same length with a similar number of trading days. A month with five Saturdays can sell more than a month with four for no other reason. When the shop was closed for a refit, a holiday or bad weather, note it beside the result rather than reading the change as a trend.

Year-over-year comparisons, such as this October against last October, remove most seasonal swings. Month-over-month comparisons react faster but move with the calendar. The U.S. Census Bureau's monthly retail trade reports show both kinds of comparison for national retail sales, if you want wider context for your own numbers.

Growth in sales is not the same as growth in profit. Higher sales from deep discounts can leave less money behind. Check prices and margins with the margin and markup calculator, see how much you need to sell to cover costs with the break-even calculator, and keep monthly totals in the income and expense tracker. For one product's performance against the stock you had, use the sell-through calculator.

Frequently asked questions

Can I use the sales growth calculator without an account?

Yes. Enter two figures and calculate. Nothing is saved or sent, so use Copy result if you want to keep the figures.

How do I calculate growth over several years?

This calculator compares two periods. Over several years, the total growth from the first year to the last is still the last year's sales minus the first year's, divided by the first year's. An average yearly rate needs a different, compound formula, which this tool does not calculate.

What if sales in the earlier period were zero?

There is no percentage growth from zero, so the calculator asks for an earlier amount above zero. Report the dollar change instead, such as "$3,000 in the first month of a new product line".

Can I compare one product or one store?

Yes. Enter that product's or store's sales for both periods. Keep the same definition in both: for example, include the same variants and the same store locations.

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