Tool directory
All tools
Browse every SolveKit utility. Each tool solves one real problem quickly, clearly, and without requiring an account.
Sleep Cycle Calculator
Find suggested bedtimes or wake times based on 90-minute sleep cycles.
Health & FitnessPercentage Calculator
Calculate percentages, percentage shares, and percentage differences.
MathPercentage Change Calculator
Measure percentage increase or decrease between two values.
MathFraction Calculator
Add, subtract, multiply, or divide two fractions and simplify the result.
MathRatio Calculator
Simplify ratios and scale both sides to a target value.
MathAverage Calculator
Find the mean, sum, count, minimum, and maximum of a number list.
MathMedian Calculator
Find the median, lower quartile, and upper quartile of a dataset.
MathStandard Deviation Calculator
Calculate population and sample standard deviation with variance.
MathQuadratic Formula Calculator
Solve real or complex roots of any quadratic equation.
MathPythagorean Theorem Calculator
Solve for any missing side of a right triangle.
MathArea Calculator
Calculate the area of rectangles, circles, triangles, and trapezoids.
MathVolume Calculator
Calculate volume for boxes, cylinders, spheres, and cones.
MathScientific Calculator
Evaluate common scientific expressions with trigonometric and logarithmic functions.
MathRandom Number Generator
Generate one or many cryptographically strong integers in a chosen range.
MathNumber Base Converter
Convert integers between binary, octal, decimal, and hexadecimal.
MathPrime Number Checker
Check whether an integer is prime and find its smallest factor.
MathAge Calculator
Calculate exact age in years, months, days, and total elapsed days.
Date & TimeDate Difference Calculator
Find the exact duration between two dates in multiple units.
Date & TimeBusiness Days Calculator
Count weekdays between two dates with optional endpoint inclusion.
Date & TimeDays Until Calculator
Count days, weeks, and hours until any future date.
Date & TimeTime Duration Calculator
Calculate elapsed hours and minutes between two times.
Date & TimeTime Zone Converter
Convert a date and time between popular IANA time zones.
Date & TimeUnix Timestamp Converter
Convert Unix seconds or milliseconds to a human-readable date and back.
Date & TimeCountdown Calculator
Create a live countdown to a selected date and time.
Date & Time