Unit Converter

Convert between different units of measurement including length, weight, temperature, volume, area, and more. Support for metric, imperial, and scientific units.

Unit Converter

Single Conversion

Value

From

Meters

(m)

Result

328.084 ft

Feet

Bulk Unit Conversions

Format: "value unit" or "value unit to unit"

Conversion Statistics

Total Conversions

Successful

Failed

3 conversion(s) failed. Check the input format and unit names.

Comprehensive unit conversion!

Convert between metric, imperial, and scientific units with high precision calculations

Understanding Measurement Systems

Unit conversion is the process of changing the value of a physical quantity from one unit to another while maintaining the same physical meaning. This involves understanding the relationships between different measurement systems and applying appropriate conversion factors.

Major Systems

Metric System (SI): International standard based on powers of 10
Imperial System: Traditional British units still used in US
US Customary: American variant of imperial system
CGS System: Centimeter-gram-second for scientific use
Natural Units: Physics units where fundamental constants = 1
Atomic Units: Convenient for atomic and molecular physics
Planck Units: Based on fundamental physical constants
Traditional Units: Historical and cultural measurements

Conversion Principles

Dimensional analysis and unit cancellation
Conversion factors and multiplication chains
Precision and significant figures preservation
Linear vs non-linear conversions
Temperature scale offset handling
Compound unit decomposition
Scientific notation for extreme values
Error propagation in calculations

Length and Distance Conversions

Metric Length Units

Small Units

1 nanometer (nm) = 10⁻⁹ m

1 micrometer (μm) = 10⁻⁶ m

1 millimeter (mm) = 10⁻³ m

1 centimeter (cm) = 10⁻² m

1 decimeter (dm) = 10⁻¹ m

Base and Large Units

1 meter (m) = base unit

1 dekameter (dam) = 10¹ m

1 hectometer (hm) = 10² m

1 kilometer (km) = 10³ m

1 megameter (Mm) = 10⁶ m

Scientific Units

1 angstrom (Å) = 10⁻¹⁰ m

1 astronomical unit (AU) = 1.496×10¹¹ m

1 light-year (ly) = 9.461×10¹⁵ m

1 parsec (pc) = 3.086×10¹⁶ m

Imperial/US Length Units

Small Units

1 inch (in) = 2.54 cm

1 foot (ft) = 12 in = 30.48 cm

1 yard (yd) = 3 ft = 91.44 cm

Large Units

1 mile (mi) = 5,280 ft = 1.609 km

1 nautical mile = 1.852 km

1 league = 3 miles

Specialized Units

1 rod = 16.5 ft

1 chain = 66 ft

1 furlong = 660 ft

1 fathom = 6 ft

Common Length Conversions

Metric ↔ Imperial

1 inch = 2.54 cm (exact)

1 foot = 30.48 cm

1 yard = 0.9144 m

1 mile = 1.609344 km

1 meter = 3.28084 ft

1 kilometer = 0.621371 mi

Quick Approximations

1 meter ≈ 1.1 yards

1 kilometer ≈ 0.6 miles

1 mile ≈ 1.6 kilometers

1 inch ≈ 2.5 cm

1 foot ≈ 30 cm

Mass and Weight Conversions

Metric Mass Units

Small Units

1 microgram (μg) = 10⁻⁶ g

1 milligram (mg) = 10⁻³ g

1 centigram (cg) = 10⁻² g

1 decigram (dg) = 10⁻¹ g

1 gram (g) = base unit

Large Units

1 dekagram (dag) = 10 g

1 hectogram (hg) = 100 g

1 kilogram (kg) = 1,000 g

1 metric ton (t) = 1,000 kg

1 megagram (Mg) = 1,000 kg

Scientific Units

1 atomic mass unit (u) = 1.66×10⁻²⁷ kg

1 electron mass = 9.11×10⁻³¹ kg

1 proton mass = 1.67×10⁻²⁷ kg

1 solar mass = 1.99×10³⁰ kg

Imperial/US Weight Units

Avoirdupois System

1 grain = 64.79891 mg

1 dram = 27.34375 grains

1 ounce (oz) = 16 drams = 28.35 g

1 pound (lb) = 16 oz = 453.59 g

1 stone = 14 lb = 6.35 kg

1 quarter = 28 lb = 12.7 kg

1 hundredweight = 112 lb = 50.8 kg

1 ton (long) = 2,240 lb = 1,016 kg

1 ton (short) = 2,000 lb = 907 kg

Troy System (Precious Metals)

1 grain = 64.79891 mg (same as avoirdupois)

1 pennyweight = 24 grains

1 troy ounce = 20 pennyweights = 31.10 g

1 troy pound = 12 troy oz = 373.24 g

Note: Troy ounce ≠ avoirdupois ounce

Temperature Conversions

Temperature Scales and Formulas

Common Scales

Celsius (°C): Water freezes at 0°, boils at 100°

Fahrenheit (°F): Water freezes at 32°, boils at 212°

Kelvin (K): Absolute scale, 0K = -273.15°C

Rankine (°R): Absolute Fahrenheit scale

Réaumur (°Ré): Historical scale, 0° to 80°

Conversion Formulas

°F = (°C × 9/5) + 32

°C = (°F - 32) × 5/9

K = °C + 273.15

°R = °F + 459.67

°Ré = °C × 4/5

Important Temperature Points

Physical Constants

Absolute zero: -273.15°C, -459.67°F, 0K

Water triple point: 0.01°C, 32.018°F, 273.16K

Water freezing: 0°C, 32°F, 273.15K

Water boiling: 100°C, 212°F, 373.15K

Human Body

Normal body temp: 37°C, 98.6°F

Fever threshold: 38°C, 100.4°F

Hypothermia: <35°C, <95°F

Hyperthermia: >40°C, >104°F

Common References

Room temperature: ~20°C, ~68°F

Hot summer day: 35°C, 95°F

Cold winter day: -10°C, 14°F

Oven baking: 180°C, 356°F

Volume and Capacity Conversions

Metric Volume Units

Small Volumes

1 microliter (μL) = 10⁻⁶ L

1 milliliter (mL) = 10⁻³ L

1 centiliter (cL) = 10⁻² L

1 deciliter (dL) = 10⁻¹ L

1 liter (L) = base unit

Large Volumes

1 dekaliter (daL) = 10 L

1 hectoliter (hL) = 100 L

1 kiloliter (kL) = 1,000 L

1 megaliter (ML) = 10⁶ L

Cubic Units

1 cm³ = 1 mL

1 dm³ = 1 L

1 m³ = 1,000 L

1 km³ = 10⁹ m³

Imperial/US Volume Units

US Liquid Measure

1 fluid ounce (fl oz) = 29.5735 mL

1 cup = 8 fl oz = 236.59 mL

1 pint = 2 cups = 473.18 mL

1 quart = 2 pints = 946.35 mL

1 gallon = 4 quarts = 3.785 L

Imperial Liquid Measure

1 imperial fl oz = 28.413 mL

1 imperial cup = 10 fl oz = 284.13 mL

1 imperial pint = 20 fl oz = 568.26 mL

1 imperial quart = 2 pints = 1.137 L

1 imperial gallon = 4 quarts = 4.546 L

Area and Pressure Conversions

Area Units

Metric Area

1 mm² = 10⁻⁶ m²

1 cm² = 10⁻⁴ m²

1 m² = base unit

1 are = 100 m²

1 hectare = 10,000 m²

1 km² = 10⁶ m²

Imperial Area

1 sq inch = 6.452 cm²

1 sq foot = 144 sq in = 929.03 cm²

1 sq yard = 9 sq ft = 0.836 m²

1 acre = 4,840 sq yd = 4,047 m²

1 sq mile = 640 acres = 2.59 km²

Specialized Units

1 barn = 10⁻²⁸ m² (nuclear physics)

1 circular mil = π/4 × 10⁻⁶ in²

1 township = 36 sq miles

1 section = 1 sq mile

Pressure Units

SI and Metric

1 pascal (Pa) = 1 N/m²

1 kilopascal (kPa) = 1,000 Pa

1 megapascal (MPa) = 10⁶ Pa

1 bar = 100,000 Pa

1 millibar = 100 Pa

Traditional Units

1 atmosphere (atm) = 101,325 Pa

1 mmHg = 133.322 Pa

1 torr = 1 mmHg

1 psi = 6,895 Pa

1 inHg = 3,386 Pa

Reference Values

Standard atmosphere: 1 atm

Sea level pressure: ~1013 mbar

Tire pressure: ~30-35 psi

Blood pressure: ~120/80 mmHg

Professional Applications and Use Cases

🔬

Scientific Research

Laboratory measurements, data analysis, experimental design, and scientific publication

🏗️

Engineering & Construction

Building design, material specifications, structural calculations, and project planning

🏥

Healthcare & Medicine

Drug dosages, medical measurements, patient monitoring, and diagnostic equipment

🍳

Cooking & Nutrition

Recipe conversions, ingredient measurements, nutritional calculations, and food service

✈️

Aviation & Transportation

Flight planning, fuel calculations, navigation, and international travel requirements

📊

Business & Finance

International trade, commodity pricing, logistics planning, and market analysis

Best Practices and Implementation Guidelines

✅ Effective Conversion

Always use exact conversion factors when available
Maintain appropriate significant figures throughout calculations
Consider the precision requirements of your application
Use dimensional analysis to verify conversion logic
Account for temperature-dependent properties when relevant
Validate results against known reference values
Document conversion factors and their sources
Consider rounding only at the final step

❌ Common Mistakes

Confusing mass and weight in different gravitational fields
Using approximate conversion factors for precise calculations
Ignoring significant figures and precision limitations
Mixing up US and Imperial units (especially volume)
Incorrect temperature scale conversions (offset vs ratio)
Not accounting for standard conditions in gas calculations
Using outdated or non-standard conversion factors
Applying linear conversions to non-linear relationships

Advanced Conversion Techniques

Dimensional Analysis Method

Step-by-Step Process

1. Identify the given quantity and desired unit

2. Set up conversion factors as fractions

3. Arrange factors so units cancel properly

4. Multiply across numerators and denominators

5. Verify that unwanted units cancel out

6. Calculate the final numerical result

Example: 50 mph to m/s

50 mi/h × (1609.34 m/mi) × (1 h/3600 s)

= 50 × 1609.34 × (1/3600) m/s

= 80,467 / 3600 m/s

= 22.35 m/s

Error Analysis and Uncertainty

Sources of Error

Measurement precision limitations

Rounding in intermediate steps

Approximation of conversion factors

Environmental condition variations

Propagation Rules

Addition/Subtraction: Add absolute errors

Multiplication/Division: Add relative errors

Powers: Multiply relative error by exponent

Functions: Use calculus-based propagation

Best Practices

Track uncertainty throughout calculation

Use appropriate significant figures

Consider systematic vs random errors

Validate with independent methods