The right number, in seconds
Free calculators for finance, real estate, construction and everyday life. Real-time results, explained methods, no sign-up.
Popular calculators
- Finance 50/30/20 budget calculator Divide your monthly take-home pay into needs, wants and savings, and compare with what you spend today.
- Finance APY calculator Convert an interest rate (APR) into APY for any compounding frequency, then see what your savings account or CD earns with monthly deposits.
- Finance Auto loan calculator Price your next car loan with the down payment, trade-in and sales tax included, and compare loan terms.
- Health BMI calculator Calculate your body mass index from your weight and height in pounds and inches or kilograms and centimeters, see your category and the weight range that matches a healthy BMI.
- Health BMR and calorie calculator Estimate your basal metabolic rate and total daily energy expenditure from your age, sex, height, weight and activity, then the calories to maintain, lose or gain weight steadily.
- Health Body fat calculator Estimate your body fat percentage from your height and neck, waist and hip measurements using the US Navy method, then your fat mass, lean mass and fitness category.
- Finance Break-even calculator Find how many units you must sell each month to cover fixed costs, and how much safety margin your sales forecast leaves.
- Construction Brick calculator Estimate how many bricks and bags of mortar a wall needs, for modular, standard, queen or king size brick.
- Finance CAGR calculator Measure the smoothed yearly growth rate between a starting and ending value, for a portfolio, revenue, a home price or any metric.
- Finance Car depreciation calculator Estimate a car's value after each year of ownership and what depreciation costs you per month.
- Real estate Closing costs calculator Estimate the buyer's closing costs on a home purchase: lender fees, title and settlement, transfer taxes and prepaid escrow, plus the total cash you need at closing.
- Finance Compound interest calculator See how an initial deposit, regular monthly contributions and an annual return grow over time, and what the result is worth after inflation.
Browse by category
Finance
Savings, interest, inflation, salary: clear financial calculators to run your budget.
24 calculators
Real estate
Mortgages, borrowing capacity, closing costs, rental yield: plan your property project with confidence.
10 calculators
Construction
Concrete, masonry, areas, materials: get the exact quantities for your job site and avoid waste.
19 calculators
Health
BMI, metabolism, body fat, heart-rate zones: numbers that help you track your fitness, without replacing advice from a health professional.
16 calculators
Everyday life
Percentages, discounts, fuel, electricity: everyday maths done in a second, without mistakes.
16 calculators
Why Omnikalc?
Instant
Results update as you type, with no page reload.
Transparent
Every formula is explained in a full guide with worked examples.
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