Free Online Calculators for Finance, Math & Tech
Swift answers.
Fast calculators for money, technology, gaming and everyday math.
171 calculators across 78 Global · 45 US · 48 UK.
Featured calculators
Download Time Calculator
Estimate file download time from its size and your connection speed. Compare the theoretical minimum with an adjustable real-world transfer estimate.
Compound Interest Calculator
Project a future balance from an initial investment, monthly contributions and an assumed interest rate. Compare compounding frequencies and separate your deposits from interest earned.
↗MathPercentage Calculator
Find a percentage of a number, express one value as a percentage of another, apply an increase or decrease, or calculate the change between two values.
↗FinanceMortgage Calculator
Estimate monthly principal and interest, total interest and repayment on a fixed-rate mortgage. Add property tax, insurance and HOA charges only if you want them included.
↗Gaming & TechPC Electricity Cost Calculator
Estimate your computer’s daily, monthly and annual electricity cost from average wall power, hours of use and your energy tariff. See both kWh and cost.
↗FinanceTip Calculator
Calculate a tip and each person’s share of the bill. Choose your percentage, optionally exclude included tax from the tip basis, and see any rounding remainder.
↗Numbers for every part of life.
Finance calculators, math tools and technology estimates.
Gaming & Tech
Plan internet demand, storage arrays, appliance energy, display density and mouse settings with explicit assumptions.
Explore collection ↗$22 HANDY TOOLSFinance
Compare loans and interest, model savings and investments, plan budgets and translate billable time into income.
Explore collection ↗π26 HANDY TOOLSMath
Solve percentages, number theory, probability, geometry and algebra with formulas and exact counting tools.
Explore collection ↗◷7 HANDY TOOLSDate & Time
Add calendar days, compare dates, total work shifts and calculate age on a specific date.
Explore collection ↗◇2 HANDY TOOLSHealth
Explore adult BMI and approximate maintenance energy with explicit screening and study limits.
Explore collection ↗An answer in seconds.
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Find your calculator ↗Health calculations with clear limits
Explore adult BMI screening or an approximate maintenance calorie range. These tools do not replace a doctor; review health decisions with a qualified professional.
Plan device energy use
Compare appliance energy costs with battery charging time: electricity consumption and recharge duration answer different questions.
Popular UK calculators
Use the local rules for net pay, property purchases and household planning.