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Percentage of a Number
A percentage describes a share of a chosen base.
Open calculator ↗Percentage Change
Percentage change measures movement relative to the starting value.
Open calculator ↗Percentage Difference
When neither observation is a natural baseline, the arithmetic average gives a symmetric denominator.
Open calculator ↗Reverse Percentage
Recover an original quantity after a known proportional increase.
Open calculator ↗Discounted Value
A discount is a reduction from the original amount.
Open calculator ↗Successive Changes
Successive percentage changes compound because the second acts on an already changed base.
Open calculator ↗Part as a Percentage
Express a measured part as a share of a reference total.
Open calculator ↗Percentage Point Gap
A percentage point gap subtracts two already expressed percentages.
Open calculator ↗Weighted Two-Value Mean
Weighted averages give observations influence in proportion to their weights.
Open calculator ↗Mean of Three Values
The arithmetic mean balances three observations equally.
Open calculator ↗Median of Three Values
The median is the middle observation in sorted order.
Open calculator ↗Geometric Mean
The geometric mean averages positive multiplicative factors.
Open calculator ↗Harmonic Mean
The harmonic mean handles rates applied to equal quantities, such as equal distances traveled at two speeds.
Open calculator ↗Population Variance
Variance measures the spread around the mean in squared units.
Open calculator ↗Sample Standard Deviation
Sample standard deviation expresses dispersion in the original measurement units.
Open calculator ↗Population Standard Deviation
Population standard deviation describes the spread of a complete three-observation set.
Open calculator ↗Z Score
A z score expresses a distance from the mean in standard deviation units.
Open calculator ↗Standard Error of Mean
Standard error describes the sampling variability of a mean under independent sampling.
Open calculator ↗Coefficient of Variation
The coefficient of variation describes dispersion relative to a positive mean.
Open calculator ↗Range
The range is the full span between the smallest and largest observations.
Open calculator ↗Root Mean Square
Root mean square summarizes the magnitude of signed observations without allowing positive and negative signs to cancel.
Open calculator ↗Linear Interpolation
Linear interpolation estimates a value on the straight line through two known points.
Open calculator ↗Slope Between Points
Slope compares vertical change with horizontal change.
Open calculator ↗Linear Equation
Solve an equation of the form ax + b = c by undoing addition and multiplication in reverse order.
Open calculator ↗Quadratic Discriminant
The discriminant indicates the real-root structure of a quadratic equation.
Open calculator ↗Positive Quadratic Root
This tool evaluates the plus branch of the quadratic formula for a real-coefficient equation.
Open calculator ↗Arithmetic Sequence Term
An arithmetic sequence adds the same difference at every step.
Open calculator ↗Arithmetic Series Sum
An arithmetic series adds a finite run of equally spaced terms.
Open calculator ↗Geometric Sequence Term
A geometric sequence multiplies by a constant ratio at every step.
Open calculator ↗Geometric Series Sum
The finite geometric sum combines a series of repeatedly scaled quantities.
Open calculator ↗Factorial
Factorial counts orderings of distinct objects.
Open calculator ↗Permutations
Permutations count ordered selections without replacement.
Open calculator ↗Combinations
Combinations count unordered selections without replacement.
Open calculator ↗Binomial Probability
A binomial model describes a fixed number of independent trials with the same success probability on each trial.
Open calculator ↗Independent Joint Probability
Multiply two probabilities to find their joint occurrence only when the events are independent.
Open calculator ↗At Least One Success
The complement of no successes gives the chance of at least one success.
Open calculator ↗Complement Probability
An event and its complement cover all outcomes without overlap.
Open calculator ↗Expected Two-Outcome Value
An expected value is a probability-weighted average across two exhaustive outcomes.
Open calculator ↗Odds to Probability
Odds in favor compare favorable outcomes to unfavorable ones.
Open calculator ↗Uniform Interval Probability
A continuous uniform distribution allocates probability in proportion to interval length.
Open calculator ↗Logarithm in Any Base
A logarithm asks which exponent raises the base to the target value.
Open calculator ↗Nth Root
An nth root reverses raising a nonnegative value to an integer power.
Open calculator ↗Ratio Scale
A proportional scale preserves a ratio while changing the reference quantity.
Open calculator ↗Direct Proportion
Direct proportion keeps y divided by x constant.
Open calculator ↗Inverse Proportion
Inverse proportion keeps the product of two quantities constant.
Open calculator ↗Remainder
The remainder is what remains after fitting the largest whole number of divisor-sized groups into a nonnegative dividend.
Open calculator ↗Greatest Common Divisor
The greatest common divisor identifies the largest exact shared grouping.
Open calculator ↗Least Common Multiple
The least common multiple gives the smallest positive count divisible by both inputs.
Open calculator ↗Distance on Number Line
Distance on a line removes direction and reports the separation of two signed positions.
Open calculator ↗Midpoint on Number Line
The midpoint lies equally far from two positions on a straight number line.
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