Average Calculator

The arithmetic mean — commonly called the average — is one of the most widely used calculations in everyday life, from grading systems and financial analysis to sports statistics and scientific measurements. This calculator lets you find the average of two or three numbers instantly, also showing you the sum and the count so you can verify the result or use those figures in further calculations. Students use it to check what score they need on a third exam to reach a target average. Investors use it to average the price paid for shares bought at different times. Coaches use it to compare average performance metrics across athletes. Small business owners use it to find the mean of their weekly sales figures. The toggle for the third value makes it flexible: enter two values for a quick two-number mean, or enable the third input to compute a three-value average. Results are shown to four decimal places to handle non-round averages precisely without unnecessary rounding.

The arithmetic mean is computed using the formula: mean = (sum of all values) ÷ (count of values). When only two values are active, the calculator sums Value 1 and Value 2 and divides by 2. When the third value is toggled on, Value 3 is added to the sum and the divisor becomes 3. The toggle approach prevents accidentally including an unused zero-value field in the calculation, which would distort the result. For example, if you enter 80 and 90 without toggling on Value 3 (which defaults to 0), you correctly get an average of 85 rather than 56.67. The sum and count are also displayed as separate outputs because they are often needed independently — for instance, when computing a weighted average manually or when verifying that all values were entered correctly. The result is rounded to four decimal places, which is sufficient precision for virtually all practical averaging tasks.