Master mathematics with our comprehensive collection of 25+ calculator formulas. From automotive calculations to financial planning, health assessments to ratio analysis - all formulas include industry standards, accuracy metrics, and real-world examples.
Professional automotive formulas for fuel economy, financing, gear ratios, and vehicle performance.
Description: Calculates monthly payments for auto loans with fixed interest rates.
Standard: Automotive Finance Industry Standard
Accuracy: Exact calculation (no rounding errors)
$25,000 car loan, 5% APR, 60 months: Monthly payment = $471.78
Description: Measures vehicle fuel efficiency in miles per gallon or liters per 100 kilometers.
Standard: EPA (Environmental Protection Agency) Standards
Accuracy: ±2-3% with accurate measurements
300 miles driven, 12 gallons used: MPG = 300/12 = 25 MPG
Description: Calculates mechanical advantage and speed reduction/increase in gear systems.
Standard: Mechanical Engineering Standards
Accuracy: Mathematically exact
40-tooth driving gear, 10-tooth driven gear: Ratio = 40/10 = 4:1
Description: Measures vehicle performance potential by comparing engine power to vehicle weight.
Standard: Automotive Performance Standards
Accuracy: ±5% depending on measurement precision
300 HP engine, 3000 lb car: Ratio = 300/3000 = 0.1 HP/lb
Description: Converts between tire size formats and calculates overall wheel diameter.
Standard: Tire and Rim Association Standards
Accuracy: ±1-2mm with standard measurements
225/60R16: Diameter = (225 × 0.60 × 2) / 25.4 + 16 = 26.6 inches
Professional-grade financial formulas for loans, investments, credit analysis, and financial planning.
Description: Measures percentage of available credit being used, major factor in credit scoring.
Standard: FICO Score Calculation Standards
Accuracy: Exact percentage calculation
$2,000 balance on $10,000 limit: Utilization = 20%
Description: Assesses borrowing capacity and financial health for lending decisions.
Standard: Consumer Financial Protection Bureau Guidelines
Accuracy: Exact percentage based on reported income
Monthly debt $2,000, income $8,000: DTI = 25%
Description: Measures annual fees charged by mutual funds or ETFs as percentage of assets.
Standard: Securities and Exchange Commission Standards
Accuracy: Exact calculation based on fund data
$1M operating expenses, $100M assets: Expense ratio = 1.00%
Description: Calculates fixed monthly payments for any type of loan with compound interest.
Standard: Standard Amortization Formula (Banking Industry)
Accuracy: Mathematically exact
$200,000 loan, 4% annual rate, 30 years: Monthly payment = $954.83
Description: Measures investment performance and profitability over time periods.
Standard: CFA Institute Financial Analysis Standards
Accuracy: Exact percentage calculation
Initial: $10,000, Final: $12,000 over 2 years: ROI = 20%, Annualized = 9.54%
Description: Measures percentage of income saved for financial health assessment.
Standard: Personal Finance Industry Standards
Accuracy: Exact percentage based on tracked amounts
$1,000 saved from $5,000 income: Savings rate = 20%
Evidence-based health formulas for fitness assessment, body composition, and wellness calculations.
Description: Measures body fat based on height and weight to assess healthy weight ranges.
Standard: WHO (World Health Organization) Guidelines
Accuracy: ±2-3% for population screening
Person weighing 70kg, height 1.75m: BMI = 70 / (1.75)² = 22.9
Description: Estimates body fat percentage using circumference measurements for accurate body composition.
Standard: US Navy Body Composition Assessment Standards
Accuracy: ±3-4% when measured correctly
Description: Calculates calorie deficit needed for safe and sustainable weight loss.
Standard: Mifflin-St Jeor Equation (Gold Standard)
Accuracy: ±10-15% for most individuals
TDEE 2500 calories, intake 2000 calories: Deficit = 500 calories/day
Description: Assesses body fat distribution and health risk related to central obesity.
Standard: WHO Health Risk Assessment Guidelines
Accuracy: ±2-3% with proper measurement technique
32-inch waist, 38-inch hips: WHR = 32/38 = 0.84
Description: Estimates realistic timeline for weight loss based on calorie deficit.
Standard: Evidence-based Weight Loss Guidelines
Accuracy: ±2-3 weeks depending on individual factors
Lose 20 lbs with 500 cal/day deficit: 20 × 3500 / (500 × 7) = 20 weeks
Essential percentage calculations for business analytics, academic grading, and mathematical analysis.
Description: Fundamental percentage calculations for proportions and ratios.
Standard: International Mathematical Standards
Accuracy: Mathematically exact
45 out of 60: (45/60) × 100 = 75%
Description: Calculates relative change between two values over time.
Standard: Statistical Analysis Standards
Accuracy: Mathematically precise
Price changed from $100 to $120: (120-100)/100 × 100 = 20% increase
Description: Calculates discount amounts and final sale prices for retail applications.
Standard: Retail Industry Standards
Accuracy: Mathematically exact
$100 item with 20% discount: Discount = $20, Sale price = $80
Description: Calculates markup percentages and selling prices for business pricing strategies.
Standard: Business Accounting Standards
Accuracy: Mathematically exact
Cost $50, selling $75: Markup = (75-50)/50 × 100 = 50%
Mathematical ratio calculations for design, engineering, and proportional analysis.
Description: Calculates proportional relationships for screens, images, and design elements.
Standard: International Standards Organization (ISO)
Accuracy: Mathematically exact
1920 × 1080 pixels: Aspect ratio = 16:9 or 1.78:1
Description: Measures engine compression for performance and efficiency analysis.
Standard: Society of Automotive Engineers (SAE) Standards
Accuracy: ±0.1 ratio units with precise measurements
Total volume 500cc, compressed 50cc: CR = 500/50 = 10:1
Description: Calculates the golden ratio for aesthetically pleasing proportions in design.
Standard: Mathematical Constant
Accuracy: Mathematically exact (irrational number)
Rectangle: 100 × 61.8 units maintains golden ratio proportions
Description: Maintains proportional relationships when scaling objects or dimensions.
Standard: Mathematical Proportion Standards
Accuracy: Mathematically exact
Photo 800×600, scale width to 400: New height = 600 × (400/800) = 300
All formulas on RatioMath are implemented using double-precision floating-point arithmetic for maximum accuracy. Results are rounded appropriately for practical use while maintaining mathematical precision. Accuracy estimates account for measurement limitations and biological/mechanical variations where applicable.
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