Calculators
Decision-support tools for sizing, cost, capacity, runtime, ownership, and other practical planning questions.
Estimate the total request capacity represented by a number of requests per worker multiplied by the number of workers. This simple model assumes every worker contributes the same capacity over the same measurement period.
Estimate the simple payback ratio of software automation by comparing labor value from saved manual hours with setup and ongoing maintenance labor costs over a selected period. This model excludes other costs and benefits.
Convert a quantity of bits into bytes using the standard relationship of 8 bits per byte. Enter a nonnegative number of bits to see the equivalent byte count.
Calculate the percentage of measured executable code covered by tests from the covered and total code units you provide. The result describes coverage for those units only.
Estimate an approximate Wald confidence interval for a sample proportion from the observed percentage, sample size, and selected z-score. The interval is approximate and may be unsuitable for rare proportions, small samples, or complex surveys.
Calculate a bounded Wald confidence interval for a population proportion from an observed sample percentage, sample size, and selected z value. The result is the lower and upper percentage bound.
Calculate the average elapsed time per completed work item from the combined cycle time and item count.
Estimate absolute error from a value and a stated relative error percentage using a direct arithmetic formula.
Calculate the percentage of inspected software units that contain one or more defects. Enter the number of defective units and the total units inspected.
Calculate the observed defects per million opportunities (DPMO) from the number of defects found and the total number of inspected opportunities. This is a descriptive rate and does not apply a sigma conversion or forecast future performance.
Estimate the ideal time to transfer a file from its size and average download speed. Choose matching units for file size and speed; the estimate excludes interruptions and network overhead.
Estimate the percentage of recorded runs that failed by entering failed and successful run counts.
Convert a file size between decimal and binary storage units using the selected source and target units.
Estimate absolute error by multiplying a value by an assumed relative error. This simple model does not simulate a specific floating-point format or operation sequence.
Add two hexadecimal numbers and view their sum in decimal form. Enter each value as a nonnegative whole number; the calculator converts the values to decimal, adds them, and displays the result.
Estimate elapsed calendar days from the start of work to completion by adding queue, active work, review, and blocked time. This simple model assumes the entered durations do not overlap.
Calculate the remainder after dividing one integer by another. Enter a dividend and a positive divisor to find the modulo result.
Calculate observed mean time between failures by dividing total operating hours by the number of failures in the same observation period. This worksheet assumes the equipment was operating throughout the entered hours and that each counted event qualifies as a failure.
Calculate how many distinct groups of a chosen size can be formed from a set, without regard to order or repetition.
Estimate the number of evenly spaced test points from a minimum value to a maximum value using a positive step size. The calculation assumes both endpoints are included and the range is divisible by the step size.
Convert a six-digit octal number to its decimal value by entering one octal digit in each place. Use leading zeros for shorter values.
Estimate the total number of tests a group of parallel workers can handle by multiplying worker count by tests per worker. This assumes every worker can complete the same number of tests during the same defined run or interval.
Estimate the value today of a future amount using an annual discount rate and a whole number of years.
Calculate the probability that at least one of several independent events occurs, using each event's probability and the number of identical trials.
Estimate the probability that a software system completes a specified number of independent operating hours without failure, using a constant failure rate derived from observed test data. This model assumes failures follow a constant-rate process and test exposure is representative.
Estimate simple return on investment as a percentage by comparing the amount invested with the value received. Enter the total investment and the resulting value. This calculation does not account for timing, taxes, inflation, risk, or cash flows between the start and end dates.
Convert red, green, and blue channel values from 0 to 255 into a six-digit hexadecimal color code.
Estimate the sample size needed to measure a population proportion at a chosen confidence level and margin of error. This planning estimate uses a normal approximation and does not account for finite population size, design effects, or nonresponse.
Estimate service availability over an observation window by comparing total measured time with unplanned downtime. This simple model reports uptime as a percentage and does not assess contractual service-level terms.
Estimate a process sigma level from the number of defects, units inspected, and opportunities for defects per unit. This simplified model uses a fixed 1.5 sigma shift and reports the result in sigma units.
Estimate defects per million opportunities (DPMO) and process yield from observed defects, inspected units, and defect opportunities per unit. The estimate uses the conventional 1.5 sigma shift assumption to report an approximate sigma level.
Estimate the downtime allowance for a service level agreement from its target availability and the length of the measurement period. The calculation assumes a fixed period, a 24-hour day, and that the entire period is covered by the availability target.
Estimate the payload size in bytes by multiplying the number of records by the bytes in each record. This assumes every record has the same size and excludes transport, protocol, and storage overhead.
Calculate the population standard deviation for exactly four numeric values. Enter each value in the same units.
Estimate how many test cases a team can execute from tester count, available hours per tester, and average minutes per test.
Estimate the storage cost of a test dataset by multiplying its size in gigabytes by a supplied storage price per gigabyte. This simple estimate excludes any additional service charges.
Estimate the total number of records generated across tests and test runs using the record count per test, tests per run, and number of runs.
Estimate the testing hours assigned to functional and regression testing from a total testing-hours budget and the percentage allocated to each activity.
Estimate direct test environment costs by multiplying the number of environments by the hours used per environment and the hourly cost. Enter consistent hours and USD rates for the same estimation period.
Estimate total test log storage in bytes from the number of events recorded per test, the average bytes per event, and the number of tests.
Compare the failure rates from two sets of tests and calculate their change in percentage points. Enter failures and total tests for each period or group.
Estimate the total time spent rerunning failed tests by multiplying the number of failed tests by the retry count and the seconds required for each retry.
Estimate test suite runtime in seconds from the number of tests, average seconds per test, and parallel workers. This simple estimate assumes tests take a similar average time and are distributed evenly across workers.
Estimate total testing cost from a one-time setup cost and the number and per-option cost of options tested.
Estimate observed software testing throughput as completed test cases per hour from the number of cases completed and elapsed testing time. This simple rate model assumes the measured interval represents the work you want to compare.
Add an offset in seconds to a timestamp in seconds and return the adjusted timestamp.
Convert a signed integer to its two's complement bit pattern for a chosen width, and decode a two's complement bit pattern as a signed integer.
Calculate the population variance of a set of equally weighted observations from their count, sum, and sum of squared values. Enter all values in the same unit.
Calculate the weighted average of three values using their corresponding nonnegative weights. The first weight must be at least 0.001 so the total weight cannot be zero.
Calculate the bitwise exclusive OR of two nonnegative integers and see which binary bit positions differ.