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114 practical online calculators
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Online2 calculators
Age and work-time calculators from the original ToolnixHub collection.
Math25 calculatorsPercentages, algebra, geometry and number calculators with transparent formulas.
Finance15 calculatorsInterest, loan, pricing, salary, profit and savings calculators.
Construction12 calculatorsMaterial and measurement estimators for common building projects.
Physics15 calculatorsMotion, force, energy, electricity, waves and mechanics calculators.
Chemistry10 calculatorsConcentration, gas, pH, dilution and laboratory formula calculators.
Statistics10 calculatorsDescriptive statistics, probability and data-analysis calculators.
Health & Wellness5 calculatorsGeneral educational estimates only; not diagnosis or treatment.
Sports5 calculatorsPace, speed, strength and sports performance calculations.
Biology5 calculatorsPopulation, growth and agriculture calculations.
Ecology3 calculatorsResource use and renewable-energy estimates with stated assumptions.
Food4 calculatorsRecipe, baking and beverage calculations.
Everyday Life3 calculatorsUseful calculations for dates, fuel, study and daily planning.
Popular calculators
Frequently useful calculations
Percentage Calculator
Calculate a percentage of any number.
Math CalculatorsLoan Payment Calculator
Estimate fixed monthly loan payments.
Finance CalculatorsBMI Calculator
Calculate adult BMI for general educational screening.
Health & Wellness CalculatorsSales Tax Calculator
Calculate tax and total price.
Finance CalculatorsCompound Interest Calculator
Calculate compound growth.
Finance CalculatorsConcrete Slab Calculator
Estimate concrete volume for a slab.
Construction CalculatorsRunning Pace Calculator
Calculate running pace and speed.
Sports CalculatorsMean Calculator
Calculate mean from a numeric list.
Statistics CalculatorsPythagorean Theorem Calculator
Find the hypotenuse from two perpendicular sides.
Math CalculatorsFuel Cost Calculator
Estimate fuel and trip cost.
Everyday Life CalculatorsMolarity Calculator
Calculate molar concentration.
Chemistry CalculatorsStandard Deviation Calculator
Calculate standard deviation from a numeric list.
Statistics CalculatorsPregnancy Due Date Calculator
Estimate a due date from LMP.
Health & Wellness CalculatorsPaint Calculator
Estimate paint volume.
Construction CalculatorsSpeed Calculator
Calculate speed from distance and time.
Physics CalculatorsRecipe Scale Calculator
Scale ingredient quantities.
Food CalculatorsComplete directory
All 114 calculators
Open a category, enter your values and review the formula beneath the result.
Online Calculators
Age and work-time calculators from the original ToolnixHub collection.
Math Calculators
Percentages, algebra, geometry and number calculators with transparent formulas.
Percentage CalculatorCalculate a percentage of any number.Open calculator →Percentage Increase CalculatorIncrease a value by a selected percentage.Open calculator →Percentage Decrease CalculatorDecrease a value by a selected percentage.Open calculator →Percentage Change CalculatorMeasure percentage change between old and new values.Open calculator →Percentage Difference CalculatorCompare two values using their average.Open calculator →Ratio CalculatorSimplify a two-number ratio.Open calculator →Proportion CalculatorSolve a:b = c:x.Open calculator →Average CalculatorFind the arithmetic mean of a list.Open calculator →Weighted Average CalculatorCalculate a weighted mean from value and weight pairs.Open calculator →Greatest Common Factor CalculatorFind the GCF of whole numbers.Open calculator →Least Common Multiple CalculatorFind the LCM of whole numbers.Open calculator →Prime Factorization CalculatorBreak a positive integer into prime factors.Open calculator →Quadratic Formula CalculatorSolve ax² + bx + c = 0.Open calculator →Slope CalculatorCalculate slope between two points.Open calculator →Midpoint CalculatorFind the midpoint between two points.Open calculator →2D Distance CalculatorFind straight-line distance between two points.Open calculator →Pythagorean Theorem CalculatorFind the hypotenuse from two perpendicular sides.Open calculator →Circle CalculatorCalculate circle area and circumference.Open calculator →Rectangle CalculatorCalculate rectangle area, perimeter and diagonal.Open calculator →Triangle Area CalculatorCalculate triangle area from base and height.Open calculator →Sphere Volume CalculatorCalculate sphere volume and surface area.Open calculator →Cylinder Volume CalculatorCalculate cylinder volume.Open calculator →Cone Volume CalculatorCalculate cone volume.Open calculator →Logarithm CalculatorCalculate a logarithm with a custom base.Open calculator →Combination CalculatorCalculate C(n,r).Open calculator →
Finance Calculators
Interest, loan, pricing, salary, profit and savings calculators.
Sales Tax CalculatorCalculate tax and total price.Open calculator →Discount CalculatorCalculate discount and sale price.Open calculator →Markup CalculatorCalculate selling price from cost and markup.Open calculator →Profit Margin CalculatorCalculate profit and margin.Open calculator →Simple Interest CalculatorCalculate simple interest.Open calculator →Compound Interest CalculatorCalculate compound growth.Open calculator →Loan Payment CalculatorEstimate fixed monthly loan payments.Open calculator →ROI CalculatorCalculate return on investment.Open calculator →CAGR CalculatorCalculate compound annual growth rate.Open calculator →Salary to Hourly CalculatorConvert annual salary to hourly rate.Open calculator →Hourly to Salary CalculatorConvert hourly rate to annual salary.Open calculator →Overtime Pay CalculatorCalculate regular and overtime pay.Open calculator →Break-Even CalculatorCalculate break-even unit quantity.Open calculator →Tip CalculatorCalculate tip, total and split.Open calculator →Zakat CalculatorEstimate zakat from eligible net assets.Open calculator →
Construction Calculators
Material and measurement estimators for common building projects.
Concrete Slab CalculatorEstimate concrete volume for a slab.Open calculator →Brick CalculatorEstimate bricks for a wall.Open calculator →Tile CalculatorEstimate floor tile quantity.Open calculator →Paint CalculatorEstimate paint volume.Open calculator →Flooring CalculatorEstimate flooring boxes.Open calculator →Gravel CalculatorEstimate gravel volume and mass.Open calculator →Roof Area CalculatorEstimate sloped roof area.Open calculator →Wallpaper CalculatorEstimate wallpaper rolls.Open calculator →Fence Post CalculatorEstimate fence posts.Open calculator →Pool Volume CalculatorEstimate rectangular pool volume.Open calculator →Pipe Volume CalculatorCalculate internal pipe volume.Open calculator →Ramp Slope CalculatorCalculate slope and angle.Open calculator →
Physics Calculators
Motion, force, energy, electricity, waves and mechanics calculators.
Speed CalculatorCalculate speed from distance and time.Open calculator →Acceleration CalculatorCalculate acceleration.Open calculator →Force CalculatorCalculate force from mass and acceleration.Open calculator →Work CalculatorCalculate mechanical work.Open calculator →Power CalculatorCalculate power from work and time.Open calculator →Kinetic Energy CalculatorCalculate kinetic energy.Open calculator →Potential Energy CalculatorCalculate gravitational potential energy.Open calculator →Momentum CalculatorCalculate linear momentum.Open calculator →Density CalculatorCalculate density.Open calculator →Pressure CalculatorCalculate pressure.Open calculator →Ohm’s Law CalculatorCalculate voltage from current and resistance.Open calculator →Wavelength CalculatorCalculate wavelength.Open calculator →Heat Energy CalculatorCalculate sensible heat.Open calculator →Torque CalculatorCalculate torque.Open calculator →Free Fall Time CalculatorEstimate ideal free-fall time.Open calculator →
Chemistry Calculators
Concentration, gas, pH, dilution and laboratory formula calculators.
Molarity CalculatorCalculate molar concentration.Open calculator →Dilution CalculatorCalculate final concentration.Open calculator →pH CalculatorCalculate pH from hydrogen-ion concentration.Open calculator →Half-Life CalculatorCalculate remaining quantity.Open calculator →Ideal Gas Law CalculatorCalculate ideal gas pressure.Open calculator →Percent Yield CalculatorCalculate percent yield.Open calculator →Grams to Moles CalculatorConvert grams to moles.Open calculator →Moles to Particles CalculatorConvert moles to particles.Open calculator →Mass Percent CalculatorCalculate mass percentage.Open calculator →Beer-Lambert Law CalculatorCalculate absorbance.Open calculator →
Statistics Calculators
Descriptive statistics, probability and data-analysis calculators.
Mean CalculatorCalculate mean from a numeric list.Open calculator →Median CalculatorCalculate median from a numeric list.Open calculator →Mode CalculatorCalculate mode from a numeric list.Open calculator →Range CalculatorCalculate range from a numeric list.Open calculator →Variance CalculatorCalculate variance from a numeric list.Open calculator →Standard Deviation CalculatorCalculate standard deviation from a numeric list.Open calculator →Z-Score CalculatorCalculate a z-score.Open calculator →Confidence Interval CalculatorEstimate a z-based confidence interval.Open calculator →Binomial Probability CalculatorCalculate exactly k successes.Open calculator →Correlation CalculatorCalculate Pearson correlation.Open calculator →
Health & Wellness Calculators
General educational estimates only; not diagnosis or treatment.
BMI CalculatorCalculate adult BMI for general educational screening.Open calculator →BMR CalculatorEstimate basal metabolic rate.Open calculator →TDEE CalculatorEstimate total daily energy expenditure.Open calculator →Pregnancy Due Date CalculatorEstimate a due date from LMP.Open calculator →Daily Water Intake CalculatorCreate a rough fluid estimate.Open calculator →
Sports Calculators
Pace, speed, strength and sports performance calculations.
Running Pace CalculatorCalculate running pace and speed.Open calculator →Cycling Speed CalculatorCalculate average cycling speed.Open calculator →One Rep Max CalculatorEstimate 1RM with the Epley equation.Open calculator →Batting Average CalculatorCalculate baseball batting average.Open calculator →Winning Percentage CalculatorCalculate winning percentage.Open calculator →
Biology Calculators
Population, growth and agriculture calculations.
Allele Frequency CalculatorCalculate allele frequency.Open calculator →Bacteria Growth CalculatorEstimate doubling growth.Open calculator →Cell Doubling Time CalculatorEstimate cell doubling time.Open calculator →Hardy-Weinberg CalculatorCalculate expected genotype frequencies.Open calculator →Plant Population CalculatorEstimate plant count from area and spacing.Open calculator →
Ecology Calculators
Resource use and renewable-energy estimates with stated assumptions.
Food Calculators
Recipe, baking and beverage calculations.
Recipe Scale CalculatorScale ingredient quantities.Open calculator →Baker’s Percentage CalculatorCalculate ingredient percentage relative to flour.Open calculator →Alcohol by Volume CalculatorEstimate beer ABV from gravity readings.Open calculator →Coffee Ratio CalculatorCalculate coffee dose from water and ratio.Open calculator →
Everyday Life Calculators
Useful calculations for dates, fuel, study and daily planning.
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