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Math & Science
Percentage, Algebra, Geometry, Fractions, Exponents, Logarithms, & Statistics.
Finance & Business
EMI, Loan, Compound Interest, CAGR, ROI, SIP, GST, & Profitability tools.
Health & Fitness
BMI, BMR, TDEE, Calorie Needs, & Heart Rate Zones.
Unit Conversions
Universal converters for length, mass, volume, temperature & cooking.
Construction & Home
Concrete, Paint, Tile, Square Footage, & Home tools.
Everyday & Fun
Age, Date, Leap Year, Bill Splitter, Dice, & GPA.
Featured Calculators
Most used tools on xCalculator.co
Percentage Calculator
Calculate percentages, percentage change, increase, and decrease with step-by-step solutions.
EMI Calculator
Calculate Equated Monthly Installment (EMI) for home, car, or personal loans with amortization table.
Compound Interest Calculator
Calculate compound interest growth with flexible compounding frequencies (monthly, quarterly, semi-annually, annually).
Area Calculator
Calculate the area of 7 geometric shapes: square, rectangle, triangle, circle, parallelogram, trapezoid, and ellipse.
BMI Calculator
Calculate Body Mass Index (BMI) and check healthy weight ranges.
CAGR Calculator
Calculate Compound Annual Growth Rate (CAGR) from initial and final values over a period.
ROI Calculator
Calculate Return on Investment (ROI) percentage from initial cost and final value.
Pythagorean Theorem Calculator
Find any missing side of a right triangle using the Pythagorean theorem (a² + b² = c²).
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Built with accuracy, speed, and privacy as first-class requirements — not afterthoughts.
Mathematically Accurate
Every formula is independently verified against authoritative references. We use Decimal.js for financial calculations to prevent floating-point errors.
Instant Results
Calculations happen in real-time as you type. No waiting, no loading spinners — just immediate, accurate answers.
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