Available
Percentage Calculator - Increase, discount and change
Percent of, share of, increase and discount with comma decimals.
Open toolCalculators
Everyday math and health calculators: percentages, rule of three, averages, BMI, calories, loans, compound interest, dates and age.
Tools in this category
Available
Rule of Three Calculator
Direct and inverse proportion solved step by step.
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Average Calculator
Simple and weighted mean of grades, prices and times.
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BMI Calculator
Body mass index with WHO band and healthy weight range.
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BMR and TDEE Calculator
Resting and daily calorie burn by Mifflin-St Jeor.
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Loan Installment Calculator
Fixed payments, total paid and interest (Price table).
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Compound Interest Calculator - Calculate your returns
Grow savings with monthly deposits: interest, totals and inflation-adjusted value.
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Days Between Dates
Exact day and week count between two dates.
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Week of the Month
See every week of any month and which week a day is in.
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Age Calculator - How Old Are You Exactly?
Enter a birth date to see age in years, months and days plus the next birthday countdown.
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Marketplace Profit Calculator
Compare profit across marketplaces at the same price, or find the price each one needs for your goal.
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Cost Breakdown & Price Calculator
List every cost, see each share % and check profit, margin and the right sale price.
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Solar Efficiency & Payback Calculator
Size panels by m2 across sunny, cloudy and rainy days, then compare investment vs kWh price for payback.
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Home Energy Consumption Calculator
Add appliances with power and daily, weekly or monthly use to estimate kWh, costs and where to save.
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RAM Latency Calculator - CAS latency in ns
Compare DDR kits by true CAS latency: MT/s and CL to nanoseconds.
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PPI Calculator - Pixel density and screen comparison
Pixel density from resolution and size: PPI, pixel pitch and up to four screens compared.
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RAID Calculator - Capacity and failure simulation
Compare RAID 0, 1, 5, 6 and 10 by usable capacity, then click disks to simulate failures.
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eDPI Calculator - Sensitivity and cm/360 converter
Compute eDPI, match sensitivity across DPIs, compare setups and estimate cm per 360 with verified yaw data.
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Concrete Calculator - Slab Volume, Bags & Cost
Calculate concrete for rectangular or round slabs. See cubic meters, bags, waste and costs with the formulas shown.
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IP Camera Storage Calculator - Bandwidth & NVR Disks
Size IP camera bandwidth, 24/7 or motion recording, retention and NVR disks from measured bitrate.
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UPS Calculator - Watts, VA & Battery Runtime
Add a PC, router and other loads to estimate UPS watts, VA and battery energy for the backup time you need.
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Installment Interest Calculator - Cash vs Monthly Payments
Reveal the effective monthly rate hidden in fixed installments, with down payment, upfront fee and first-payment timing.
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Opportunity Cost Calculator - Compare Two Choices
Compare buying, renting or two projects with upfront costs, monthly cash flows, resale value and a discount rate.
Open toolHow to calculate
- Pick the calculator that matches your question.
- Type values in your local format — commas work as decimals.
- Read the highlighted result and its chart when shown.
Good to know
Are the results exact?
They use standard formulas with sensible rounding for everyday use, not certified measurements.
Do my numbers leave my device?
No. Every calculation runs in your browser and nothing is uploaded.