Free Online Calculators
Finance, health, date, maths, statistics and unit-conversion calculators that show their working rather than just an answer. Each one runs in the page, so results appear as you type and nothing you enter is recorded.
101 tools in this category · free · no signup · no watermarks
Financial
Loan / EMI CalculatorEstimate monthly payments (EMI), total interest and amortisation.EMI CalculatorWork out equated monthly instalments for any loan.Mortgage CalculatorEstimate home-loan payments including taxes and insurance.Simple Interest CalculatorCalculate simple interest and the total amount due.Compound Interest CalculatorSee how investments grow with compounding over time.SIP CalculatorProject mutual-fund SIP returns from monthly investments.Investment CalculatorProject returns on a lump-sum investment.Savings CalculatorPlan how long it takes to reach a savings goal.Retirement CalculatorEstimate the nest egg you need for retirement.Inflation CalculatorSee how inflation changes purchasing power over time.Currency ConverterConvert between world currencies at live exchange rates.Tax CalculatorEstimate income tax from your earnings.VAT / GST CalculatorAdd or remove VAT/GST from a price.Discount CalculatorFind the sale price and how much you save.Profit Margin CalculatorWork out margin, markup and selling price.Break-even CalculatorFind the units needed to cover your costs.ROI CalculatorMeasure return on investment as a percentage.Salary CalculatorConvert between hourly, monthly and annual pay.Commission CalculatorCalculate sales commission earnings.Tip CalculatorSplit the bill and work out the tip per person.
Health
BMI CalculatorCalculate Body Mass Index in metric or imperial units.BMR CalculatorEstimate your Basal Metabolic Rate.Calorie CalculatorFind your daily calorie needs (TDEE).Body Fat CalculatorEstimate body fat percentage (US Navy method).Ideal Weight CalculatorFind a healthy weight range for your height.Water Intake CalculatorEstimate how much water to drink daily.Pregnancy Due DateEstimate your baby's due date.Ovulation CalculatorFind your most fertile days.Heart Rate CalculatorFind your max heart rate and training zones.Macro CalculatorSplit daily calories into protein, carbs and fat.Protein Intake CalculatorEstimate daily protein needs.Pace CalculatorCalculate running pace, time and distance.Calories BurnedEstimate calories burned during exercise.
Date & Time
Age CalculatorFind exact age and the time between two dates.Date Difference CalculatorCount the days, weeks and months between two dates.Time Duration CalculatorAdd or subtract times and find durations.Business Days CalculatorCount working days between dates.Countdown TimerCount down to an event or date.Time Zone ConverterConvert times across world time zones.Week Number CalculatorFind the ISO week number for any date.Birthday CalculatorCount down to your next birthday.Pregnancy Weeks CalculatorTrack how far along a pregnancy is.Working Hours CalculatorTotal work hours from clock-in and clock-out times.
Math
Scientific CalculatorTrigonometry, logarithms, powers, factorials and constants.Percentage CalculatorWork out percentages, increases, decreases and ratios.Fraction CalculatorAdd, subtract, multiply and simplify fractions.Matrix CalculatorMatrix addition, multiplication and determinants.Equation SolverSolve linear and simple algebraic equations.Quadratic SolverSolve quadratic equations and find the roots.Log CalculatorCompute logarithms in any base.Factorial CalculatorCompute n! for any non-negative integer.Prime Number CalculatorCheck primality and factorise a number.GCD / LCM CalculatorFind the greatest common divisor and least common multiple.Complex Number CalculatorArithmetic with complex numbers.Derivative CalculatorDifferentiate functions symbolically.Integral CalculatorIntegrate functions definitely or indefinitely.Limit CalculatorEvaluate the limit of a function.Trigonometry CalculatorSolve angles and sides of triangles.Probability CalculatorCompute probabilities of events.
Unit Conversion
Unit ConverterConvert length, weight, temperature, area, volume, speed and data.Temperature ConverterConvert Celsius, Fahrenheit and Kelvin.Pressure ConverterConvert PSI, bar, pascal and atm.Power ConverterConvert watts, horsepower and kilowatts.Energy ConverterConvert joules, calories and kWh.Data Speed ConverterConvert Mbps, MB/s and Gbps.Fuel Economy ConverterConvert MPG, km/L and L/100km.Frequency ConverterConvert Hz, kHz, MHz and GHz.
Education
GPA CalculatorCalculate semester GPA from grades and credits.CGPA CalculatorCalculate cumulative GPA across semesters.Grade CalculatorWork out final grades from weighted scores.Attendance CalculatorTrack attendance percentage and required classes.Marks Percentage CalculatorConvert marks to a percentage.Study Time CalculatorPlan study hours toward a goal.
Statistics
Statistics CalculatorMean, median, mode, variance and standard deviation.Z-Score CalculatorCalculate the standard score of a value.Correlation CalculatorCompute the correlation between two variables.Regression CalculatorFit a linear regression line.Probability CalculatorProbability of events and combinations.
Construction
Concrete CalculatorEstimate concrete volume for slabs and footings.Paint CalculatorEstimate paint needed for a room.Tile CalculatorWork out tiles needed for a floor or wall.Brick CalculatorEstimate bricks needed for a wall.Flooring CalculatorEstimate flooring material and cost.Roofing CalculatorEstimate roofing area and materials.Stair CalculatorCalculate stair rise, run and stringer.Cement CalculatorEstimate cement, sand and aggregate.
Programming
Number Base ConverterConvert between binary, octal, decimal and hex.Binary CalculatorArithmetic and bitwise ops on binary numbers.ASCII ConverterConvert text to and from ASCII codes.Unicode ConverterConvert text to Unicode code points.CIDR CalculatorCompute network ranges from CIDR notation.Subnet CalculatorPlan subnets, masks and host ranges.Hash GeneratorGenerate SHA-1, SHA-256, SHA-384 and SHA-512 hashes.Timestamp ConverterConvert Unix timestamps to dates.
Business
Invoice CalculatorTotal invoices with tax and discounts.Profit CalculatorCompute profit from cost and revenue.Sales Tax CalculatorAdd sales tax to a price.Commission CalculatorCalculate sales commission payouts.Depreciation CalculatorStraight-line and reducing-balance depreciation.Inventory CalculatorTrack stock value and reorder points.Break-even CalculatorFind the break-even point for a product.
Why these tools run in your browser
Most online tools work by uploading your file to a server, processing it there, and sending the result back. That means a copy of your document exists on a machine you do not control, governed by a retention policy you did not write. Toolsnest inverts that: the code is downloaded to you, and your file stays put. You can verify this yourself — open your browser's Network tab, run any tool on this page, and watch that no request carries your file.
No accounts, no limits, no watermarks
Because there is no server doing the work, there is no per-task cost to recover — so there is no daily task cap, no queue, no watermark on the output and no upgrade prompt. Batch sizes are limited only by your own device's memory.
Explore more
Browse the full catalogue of every Toolsnest tool, or read the guides for step-by-step walkthroughs.