Equal-share average
Best when each observation should count equally. Add everything, divide by the count.
PASTE · COMPARE · UNDERSTAND
Average Calculator
Find the ordinary mean, weighted average, combined group average, target average, or average rate of change — with the working shown and common averaging mistakes called out.
5 modesone workbench
100klist values max
localno upload
AVERAGE WORKBENCH
Choose the average problem you actually have
Paste a spreadsheet column or separate values with commas, spaces, semicolons, tabs, or new lines. Invalid tokens are rejected instead of silently ignored.
MIN → MAX—
RANGE—
MIDRANGE—
GEOMETRIC MEAN—
HARMONIC MEAN—
RMS—
TRIMMED MEAN—
SAMPLE SD—
DISTRIBUTION
No chart yet.See where the mean and median sit
Show the working
- Enter values above.
One pair per line. Weights may be counts, credits, quantities, or percentages such as 92:40%. They do not need to add to 100.
| Value | Weight | Share | Value × weight |
|---|---|---|---|
| Calculate to see contributions. | |||
This fixes the classic “average of averages” mistake. Group size must be a positive whole number.
Example: a class of 10 averaging 80 and a class of 30 averaging 60 combine to 65, not 70.
Average rate of change is the secant slope: Δy ÷ Δx. It describes change over an interval, not an instantaneous derivative.
WHICH AVERAGE?
Use the statistic that matches the question
Different importance
Use for grades with credit hours, quantities at different prices, ratings with vote counts, and combined group means.
Outlier-resistant center
Useful when extreme values can drag the mean away from a typical observation, such as income or house-price data.
Multiplicative or rate problems
Geometric mean suits positive multiplicative factors; harmonic mean is useful for positive rates under specific equal-distance or reciprocal settings.
DAILY AVERAGE
One mental-average challenge per UTC day
Deterministic practice — everyone gets the same question for the date.
TODAY'S VALUES—
What is the arithmetic mean?
Choose an answer.
Method, precision & limitations
Arithmetic and weighted means
Simple mean uses Σx ÷ n. Weighted mean uses Σ(wx) ÷ Σw. Combined group averages are the same weighted-mean problem with group size as the weight.
Numerical handling
List sums use compensated summation. Geometric mean uses logarithms to reduce overflow risk. Root-mean-square is scaled before squaring. Results still use IEEE-754 JavaScript numbers, so extremely large or tiny values can lose precision.
Trimmed mean
The selected percentage is removed from each tail using a whole-number floor count. On short lists, a 10% trim may remove zero values; the result then equals the ordinary mean.
Scope
This is an educational calculator. It does not decide whether a mean is statistically appropriate, repair biased data, infer missing weights, or replace a documented statistical workflow for regulated or scientific analysis.