Average Calculator
Calculate the weighted arithmetic mean of up to five values using their counts. Enter each value and a positive count. Set unused counts to 1 and their values to 0.
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Calculators
Calculators
Decision-support tools for sizing, cost, capacity, runtime, ownership, and other practical planning questions.
Ballot Paper Budget Calculator
Estimate ballot paper spending from the number of ballots, unit cost per ballot, and any shipping cost. This simple budget model excludes other election expenses.
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At Least One Success Binomial Probability Calculator
Calculate the probability of at least one success across a fixed number of independent trials with the same success probability.
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Break-Even Point Calculator
Estimate how many units must be sold for revenue to cover fixed costs, using a fixed selling price per unit and variable cost per unit. This simple model assumes one product, constant prices and costs, and no taxes or other revenue.
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Campaign Budget Allocation Calculator
Calculate the share of a campaign budget allocated at a chosen percentage. This simple planning estimate assumes the percentage applies to the full budget entered.
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Campaign Budget per Volunteer Calculator
Divide a campaign budget in currency units by the number of volunteers to estimate the budget amount per volunteer. This simple allocation measure assumes the full entered budget is divided evenly across the volunteers counted.
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Campaign Canvassing Route Distance Calculator
Estimate the distance covered on a canvassing route by multiplying the number of route segments by the average distance per segment. Enter segment length in kilometers.
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Campaign Cost per Vote Calculator
Estimate average campaign spending per vote received by dividing total campaign cost by the number of votes received. Enter both amounts in consistent currency and vote units. The result is an average and does not show which campaign activities caused each vote.
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Campaign Event Cost Calculator
Estimate the total direct cost of a campaign event schedule by multiplying the number of events by the average cost per event. This simple planning estimate assumes each event has the same cost and excludes expenses not included in that average.
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Campaign Leaflet Print Quantity Calculator
Estimate the total number of campaign leaflets to print by multiplying planned events, attendees per event, and leaflets per attendee.
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Compound Annual Growth Rate Calculator
Calculate the annualized rate of change between a starting value and ending value over a stated number of years. The result assumes a positive starting value, a nonnegative ending value, and steady compounding across the period.
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Sample Proportion Confidence Interval Calculator
Estimate an approximate Wald confidence interval for a sample proportion using the observed percentage, sample size, and selected z value.
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Correlation Coefficient Calculator
Estimate Pearson’s correlation coefficient from covariance and the standard deviations of two variables. Both standard deviations must be greater than zero.
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Countdown Duration Calculator
Calculate the time remaining until a target date and time from a starting date and time, using the number of days, hours, minutes, and seconds between the two timestamps you provide.
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Demographic Percentage Calculator
Calculate what percentage a demographic group represents of a total population using a group count and the population total.
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Election Ballot Cost Calculator
Estimate total ballot cost by multiplying the number of ballots by the cost per ballot. This simple estimate assumes one uniform per-ballot cost and excludes other election expenses.
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Expected Value Calculator
Estimate the average outcome of a simple uncertain event by weighting each possible result by its probability. Enter the outcome values in consistent units and the probability of each outcome as a percentage.
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Exponential Growth Calculator
Estimate a quantity after repeated growth periods using an initial amount, a percentage growth rate per period, and the number of periods. This discrete compounding model assumes the same rate applies in every period.
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Fraction Calculator
Add, subtract, multiply, or divide two fractions and view the result as a decimal.
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Gini Coefficient Calculator
Estimate the Gini coefficient from grouped population shares and cumulative income shares. Enter each group's population percentage and its corresponding income percentage in ascending income order.
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Income Inequality Ratio Calculator
Compare the average income of a higher-income group with that of a lower-income group using the two group averages you provide. This simple ratio is a descriptive comparison, not a full measure of income inequality across a population.
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Three-Value Median Calculator
Find the median of exactly three values. The median is the middle value after ordering the three inputs.
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Net Present Value Calculator
Estimate the present value of three annual net cash flows after an initial outlay, using the annual discount rate you provide. This is a simplified arithmetic model and does not assess whether an investment is suitable.
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Odds Calculator
Convert a probability percentage into decimal odds and the equivalent fractional odds. Enter a probability from 0.01% to 99.99%. The calculation assumes the probability is already known and does not estimate or recommend an outcome.
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Opportunity Cost Calculator
Compare the value you expect from a chosen option with the value of the best alternative you would give up. Enter both values in the same units and time period to estimate the opportunity cost.
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Payback Period Calculator
Estimate how many years it takes for a one-time investment to be recovered from steady annual net cash benefits. Enter the initial investment and expected annual benefits and costs.
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Per Capita Calculator
Divide a total amount by the population to calculate the amount per person. Use consistent units and define the population and time period before entering values.
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Percent of a Number Calculator
Find a percentage of a number by entering the percentage and the number. The result is the amount represented by that percentage.
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Percentage of a Number Calculator
Find the value represented by a percentage of a number. Enter a percentage and a number to calculate the corresponding amount.
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Percentage Decrease Calculator
Calculate the amount and percentage by which an original value decreases to a new value. Enter both values in the same units. The percentage decrease is measured against the original value.
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Percentage Difference Calculator
Calculate the percentage difference between two non-negative values by comparing their absolute difference with their average. Enter both values in the same units.
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Percentage Increase Calculator
Calculate the percentage increase from an original value to a new value using the difference divided by the original value.
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Percentage Point Change Calculator
Calculate the percentage point change between an initial percentage and a later percentage by subtracting the initial value from the later value.
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Percentage Points Calculator
Calculate the change between two percentages in percentage points, and see the relative percent change from the starting value.
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Percentile Rank Calculator
Estimate the percentile rank of a score by comparing it with the number of observations below and equal to it in a reference group.
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Policy Cost per Person Calculator
Divide a policy's total cost by the number of people affected to estimate the average cost per person. Enter both amounts in consistent currency and population units.
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Population Density Calculator
Calculate the average number of people per unit of land area by dividing population by area. Enter population and land area in matching units to estimate people per square kilometer or square mile.
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Population Growth Calculator
Estimate the change in population over time using a starting population and an annual growth rate. This compound-growth model assumes the rate stays constant and does not account for migration or other demographic changes separately.
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Independent Trial Probability Calculator
Calculates the probability of at least one occurrence across a specified number of independent trials, given the probability of the event on each trial.
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Proportion Calculator
Solve a proportion by entering three known positive values. The calculator finds the missing fourth value using equivalent ratios.
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Public Meeting Cost Calculator
Estimate the direct cost of a public meeting by multiplying the number of attendees by the cost per attendee. This simple model assumes the per-attendee figure captures the costs you want to include.
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Ratio Calculator
Compare two nonnegative quantities by calculating the first quantity per one unit of the second, with a safe result when both quantities are zero.
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Return on Investment Calculator
Calculate simple return on investment as a percentage from an initial investment, ending value, and additional costs. This model treats the ending value as the value received or held at the end of the measurement period and subtracts the initial investment and additional costs to estimate net gain or loss.
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Four-Value Population Standard Deviation Calculator
Calculate the population standard deviation for exactly four numeric values using their mean and squared deviations.
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Survey Response Rate Calculator
Calculate the percentage of invited people who completed your survey using the number invited and the number of completed responses.
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Time Duration Calculator
Calculate elapsed time from a start time to an end time using a 24-hour clock. If the end time is earlier than the start time, the calculator treats it as the following day.
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Unit Rate Calculator
Divide a total amount by the number of units to find the rate per unit. Enter a positive quantity and its total amount to calculate a comparable unit rate.
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Population Variance Calculator
Calculate population variance from a set of numeric observations using their count, sum, and sum of squared values.
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Weighted Average Calculator
Calculate the weighted average of three values using their relative weights. Enter each value and a positive weight to see the combined result.
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Z Score Calculator
Calculate how many standard deviations an observed value is above or below a supplied mean.
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