mathematics calculator
Average Calculator
Calculate arithmetic, weighted, geometric, and harmonic means plus median, mode, range, and RMS.
8 statistics modes
Calculate averages and summary values
Result
Enter values and choose Calculate.
Formula version 1.0.0 · Up to 1,000 finite values.
Descriptive statistics
Average formulas and worked examples
Different averages answer different questions. Choose a mode that matches the data and interpretation.
Arithmetic and weighted means
mean = Σx / n; weighted mean = Σ(wx) / Σw.
Example: mean of 2, 4, 9 is 5.
Geometric and harmonic means
geometric = (Πx)^(1/n); harmonic = n / Σ(1/x).
Geometric inputs cannot be negative; harmonic inputs cannot be zero.
Median and mode
The median is the middle sorted value (or mean of two middle values). Modes are the most frequent values.
Example: 1, 2, 2, 7 has median 2 and mode 2.
Range and RMS
range = max − min; RMS = √(Σx²/n).
How to use this calculator
- Choose a Calculation type that matches the question you need to answer.
- Enter 1 to 1,000 finite numbers in Values, separated by commas, spaces, semicolons, or new lines.
- For Weighted average, enter one nonnegative number in Weights for every value; the total weight must be greater than zero.
- Select Calculate, then read Result together with Count, Sum, Min, Max, and Show calculation steps.
Symbols and units
| Symbol | Meaning | Unit or domain |
|---|---|---|
x | One value in the entered data set | Same unit as the data |
n | Number of entered values | Count from 1 to 1,000 |
Σ | Sum of the following terms over all values | Depends on the summed term |
w | A nonnegative weight assigned to a value | Relative weight |
Π | Product of all entered values | Product of input units |
min / max | Smallest / largest entered value | Same unit as the data |
RMS | Root mean square, √(Σx²/n) | Same unit as the data |
Checked examples
Arithmetic mean of four values
Inputs: Calculation type: Arithmetic mean; Values: 2, 4, 6, 8
Calculation: (2 + 4 + 6 + 8) ÷ 4 = 20 ÷ 4
Result: 5
The four values have an arithmetic mean of 5.
Check: average-general.test.ts — calculates arithmetic and weighted means
Weighted average
Inputs: Calculation type: Weighted average; Values: 78, 122, 131; Weights: 200, 300, 500
Calculation: (78×200 + 122×300 + 131×500) ÷ (200 + 300 + 500) = 117,700 ÷ 1,000
Result: 117.7
Larger weights make 131 contribute more to the result than 78 or 122.
Check: average-general.test.ts — calculates arithmetic and weighted means
Median and tied modes
Inputs: Calculation type: Mode; Values: 1, 1, 2, 2, 3
Calculation: 1 occurs twice; 2 occurs twice; 3 occurs once.
Result: 1, 2
The data set is bimodal because two values share the highest frequency.
Check: average-general.test.ts — returns multiple modes and range
Assumptions, rounding, and limits
- Tokens are parsed as numbers after splitting on commas, spaces, semicolons, or new lines; an empty or nonnumeric token set is invalid.
- Arithmetic mean, median, mode, range, and RMS accept finite negative, zero, and positive values.
- Geometric mean rejects negative values; if any value is zero, the result is zero.
- Harmonic mean rejects zero because reciprocals of zero are undefined.
- Weighted average requires matching value and weight counts, nonnegative weights, and a positive total weight.
- The mode result can contain more than one value when frequencies tie.
- Calculations retain JavaScript numeric precision; the interface rounds displayed values to at most 10 decimal places using half-up display formatting.
- An average describes the supplied data only; it does not establish causation, sampling quality, or which statistic is appropriate for a decision.
Frequently asked questions
Which average should I use?
Use the arithmetic mean for ordinary additive data, a weighted mean when observations contribute unequally, the geometric mean for multiplicative growth factors, and the harmonic mean for rates over equal quantities. Median is often more resistant to extreme values.
Why does the geometric or harmonic mean reject my values?
This implementation does not accept negative geometric-mean inputs, and the harmonic mean cannot include zero because it sums reciprocals.
Can a data set have more than one mode?
Yes. The calculator returns every value tied for the highest frequency, so a data set can be bimodal or multimodal.
Sources and review
- National Institute of Standards and Technology: NIST Digital Library of Mathematical Functions: Means — Accessed 2026-10-25
- National Institute of Standards and Technology: Measures of Location — Accessed 2026-10-25
- Formula version
- average.general@1.0.0
- Formula review
- Formula review: Equatara formula review
- Editorial review
- Editorial review: Equatara editorial review
- Last verified
- 2026-10-25
- Applicability
- Global, unit-neutral descriptive mathematics
- Next review
- On material formula/source change, or by 2028-10-25.
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Found a problem?
Report a formula, result, example, source, or accessibility issue through the calculator correction process. Do not include sensitive input values.