Unit Converters — Free Online Calculators
Unit conversions come up constantly — in engineering specs, cooking recipes, scientific papers, travel planning, and everyday calculations. Getting them wrong can mean failed experiments, wasted materials, or missed deadlines. Our converters apply precise mathematical formulas so you can trust the results.
Browse 51 conversion calculators across 8 measurement categories below. Each converter includes the formula used, a pre-computed conversion table for common values, and step-by-step instructions. All calculations happen instantly in your browser.
Length Conversions
Kilometers to Miles
Multiply the km value by 0.621371
Miles to Kilometers
Multiply the miles value by 1.60934
Meters to Feet
Multiply the meters value by 3.28084
Feet to Meters
Multiply the feet value by 0.3048
Centimeters to Inches
Multiply the cm value by 0.393701
Inches to Centimeters
Multiply the inches value by 2.54
Yards to Meters
Multiply the yards value by 0.9144
Meters to Yards
Multiply the meters value by 1.09361
Millimeters to Inches
Multiply the mm value by 0.0393701
Inches to Millimeters
Multiply the inches value by 25.4
Weight Conversions
Kilograms to Pounds
Multiply the kg value by 2.20462
Pounds to Kilograms
Multiply the lbs value by 0.453592
Ounces to Grams
Multiply the oz value by 28.3495
Grams to Ounces
Multiply the grams value by 0.035274
Stone to Kilograms
Multiply the stone value by 6.35029
Kilograms to Stone
Multiply the kg value by 0.157473
Metric Tons to Pounds
Multiply the metric tons value by 2204.62
Pounds to Metric Tons
Multiply the lbs value by 0.000453592
Temperature Conversions
Speed Conversions
Miles per Hour to Kilometers per Hour
Multiply the mph value by 1.60934
Kilometers per Hour to Miles per Hour
Multiply the km/h value by 0.621371
Meters per Second to Kilometers per Hour
Multiply the m/s value by 3.6
Knots to Kilometers per Hour
Multiply the knots value by 1.852
Knots to Miles per Hour
Multiply the knots value by 1.15078
Area Conversions
Square Feet to Square Meters
Multiply the sq ft value by 0.092903
Square Meters to Square Feet
Multiply the sq m value by 10.7639
Acres to Hectares
Multiply the acres value by 0.404686
Hectares to Acres
Multiply the hectares value by 2.47105
Square Miles to Square Kilometers
Multiply the sq mi value by 2.58999
Square Kilometers to Square Miles
Multiply the sq km value by 0.386102
Volume Conversions
Liters to Gallons (US)
Multiply the liters value by 0.264172
Gallons (US) to Liters
Multiply the gallons value by 3.78541
Milliliters to Fluid Ounces
Multiply the ml value by 0.033814
Fluid Ounces to Milliliters
Multiply the fl oz value by 29.5735
Cups to Milliliters
Multiply the cups value by 236.588
Milliliters to Cups
Multiply the ml value by 0.00422675
Data Conversions
Gigabytes to Megabytes
Multiply the GB value by 1000
Megabytes to Gigabytes
Multiply the MB value by 0.001
Terabytes to Gigabytes
Multiply the TB value by 1000
Gigabytes to Terabytes
Multiply the GB value by 0.001
Kilobytes to Megabytes
Multiply the KB value by 0.001
Megabytes to Kilobytes
Multiply the MB value by 1000
Time Conversions
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