Calculators
Markup Calculator
Calculate margin, markup, profit and a selling price.
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Free online utilities
Free online calculators.
Straightforward tools that work right here on your phone, tablet or computer. No account, no AI, no nonsense.
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KitLumo Calculators
Choose the calculation that matches the question
KitLumo’s calculators cover money, tax, health, home, time and everyday maths. Start by deciding whether you need a total, a difference, a rate, a date interval or an estimate before choosing a tool.
Rates, tax treatment, health guidance and lender terms can vary by location and situation. Use the number as a clear starting point, keep the inputs beside it and confirm an important decision against current local or professional information.
- Check the unit, currency and date behind every input.
- Change one input at a time when comparing scenarios.
- Keep the original figures so the result can be checked later.
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Understand the result, not just the number.
Short, plain-language guides explain the assumptions, privacy and limits behind the most important KitLumo tools.
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74 tools
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Calculators
Unit Converter
Convert common length, weight, volume and temperature units.
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Calculators
Loan Calculator
Estimate monthly repayments, total interest and total cost.
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Calculators
Date Difference
See the time between two dates in days and weeks.
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Calculators
Percentage Calculator
Calculate a percentage, share, or percentage increase.
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Calculators
VAT Calculator
Add VAT to a price or extract it from a VAT-inclusive total.
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Calculators
Discount Calculator
See the sale price, amount saved and optional tax in one view.
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Calculators
Tip Splitter
Split a bill and tip fairly across any number of people.
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Calculators
Compound Interest
Estimate investment growth with recurring contributions.
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Calculators
Business Days
Count weekdays between dates and exclude your own holidays.
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Calculators
Age Calculator
Calculate an exact age in years, months and days.
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Calculators
Fuel Cost
Estimate fuel needed and the cost of a one-way or return trip.
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Calculators
Time Duration
Find the time between two dates and subtract a break.
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Calculators
Mortgage Calculator
Estimate monthly home-loan payments, interest and total repayment.
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Calculators
Salary Converter
Convert annual pay into monthly, weekly, daily and hourly amounts.
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Calculators
Average Calculator
Find the mean, median, sum and range of a list of numbers.
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Calculators
Ratio Calculator
Simplify a ratio and compare each value as a share of the whole.
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Calculators
Pace Calculator
Calculate running pace, speed and equivalent pace per mile.
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Calculators
Electricity Cost
Estimate what an appliance costs to run per day or period.
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Calculators
Break-even Calculator
Find how many units you must sell to cover your costs.
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Calculators
Scientific Calculator
Do everyday and advanced maths directly in your browser.
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Calculators
BMI Calculator
Estimate body mass index from adult height and weight.
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Calculators
GPA Calculator
Work out an unweighted 4.0 grade-point average.
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Calculators
Time Zone Converter
Convert a date and time between major cities worldwide.
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Calculators
Online Timer
Set a simple countdown timer for any task.
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Calculators
Online Stopwatch
Track elapsed time with start, pause and reset.
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Calculators
Calorie Calculator
Estimate adult daily calorie needs using your activity level.
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Calculators
Sales Tax Calculator
Add a local sales-tax, VAT or GST rate to a price.
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Calculators
Overtime Pay Calculator
Estimate gross regular and overtime pay for a work week.
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Calculators
Retirement Calculator
See how savings and monthly contributions could grow over time.
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Calculators
Grade Calculator
Work out a weighted class grade from scores and assignments.
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Calculators
Debt Payoff Calculator
Estimate how long a fixed monthly payment takes to clear debt.
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Calculators
Fraction Calculator
Add, subtract, multiply or divide and simplify two fractions.
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Calculators
Square Footage Calculator
Find area for rooms, floors, gardens and projects in any unit.
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Calculators
Savings Goal Calculator
Estimate how long it could take to reach a savings target.
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Calculators
ROI Calculator
Calculate profit, return on investment and investment multiple.
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Calculators
Debt-to-Income Calculator
Compare monthly debt payments with gross monthly income.
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Calculators
Fuel Economy Converter
Convert L/100 km, US MPG, UK MPG and kilometres per litre.
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Calculators
Loan Amortization Calculator
See payment, interest and balance details for the first year of a loan.
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Calculators
Mortgage Overpayment Calculator
Estimate time and interest saved by adding an extra monthly payment.
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Calculators
Net Worth Calculator
Add assets and liabilities to see a simple personal net-worth total.
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Calculators
Recipe Converter
Scale ingredient amounts up or down for the number of servings you need.
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Calculators
Paint Calculator
Estimate paint litres for walls, coats and coverage.
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Calculators
Concrete Calculator
Work out concrete volume for a slab with waste allowance.
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Calculators
Volume Calculator
Convert length, width and height into useful volume units.
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Calculators
Ideal Weight Calculator
Get a height-based reference range in kilograms and pounds.
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Calculators
Water Intake Calculator
Estimate everyday water intake from weight and activity.
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Calculators
Commission Calculator
Calculate commission and estimated total gross pay.
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Calculators
Rent Split Calculator
Split rent and bills equally between housemates.
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Calculators
Reading Time Calculator
Count words and estimate how long a text takes to read.
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Calculators
Price Per Unit Calculator
Compare product prices by working out the cost of each unit.
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Calculators
Profit Margin Calculator
Calculate profit and profit margin from revenue and costs.
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Calculators
Pay Raise Calculator
See your new annual and monthly pay after a raise.
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Calculators
Savings Rate Calculator
Find the percentage of your monthly income you save.
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Calculators
Emergency Fund Calculator
Set a savings target based on your essential monthly costs.
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Calculators
Down Payment Calculator
Work out a home down payment and remaining loan amount.
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Calculators
CAGR Calculator
Calculate the compound annual growth rate of an investment.
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Calculators
Inflation Calculator
Estimate future costs and the effect on buying power.
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Calculators
Depreciation Calculator
Estimate straight-line depreciation for an asset over time.
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Calculators
Simple Interest Calculator
Calculate interest without compounding.
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Calculators
Subscription Cost Calculator
See how recurring monthly subscriptions add up over time.
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Calculators
Rent Affordability Calculator
Set a rent budget based on your monthly take-home income.
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Calculators
Circle Calculator
Find circle area, circumference and diameter from its radius.
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Calculators
Triangle Calculator
Calculate the area of a triangle from its base and height.
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Calculators
Cylinder Volume Calculator
Find the volume and base area of a cylinder.
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Calculators
PPI Calculator
Calculate pixel density from screen resolution and size.
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Calculators
Date Add Calculator
Add or subtract days from any calendar date.
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Calculators
Week Number Calculator
Find the ISO week number for a date.
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Calculators
Work Hours Calculator
Calculate paid working time after unpaid breaks.
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Calculators
Due Date Calculator
Estimate a due date from the first day of a last period.
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Calculators
Heart Rate Zone Calculator
Estimate training heart-rate zones from your age.
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Calculators
Protein Intake Calculator
Estimate a daily protein target from body weight.
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Calculators
Calorie Burn Calculator
Estimate activity energy use from METs, time and weight.
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Calculators
Shipping Cost Calculator
Estimate a parcel cost from weight, rate and handling charge.
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KitLumo is built around small, focused utilities. No login walls, no artificial limits and no AI layer where a reliable tool will do.
Every tool currently available works directly on the phone, tablet or computer you are using. Anything you type, paste, calculate or open in a tool is not sent to us, and KitLumo does not save a copy.
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