Conversion Calculator

Convert between various units of measurement including length, weight, and temperature. Easy unit conversion tool.

Convert between common units of measurement.

About This Calculator

Bridge the gap between measurement systems with the Unit Conversion Calculator. Whether you're following a recipe from another country, planning international travel, working on a science project, or comparing product specifications, this tool lets you switch seamlessly between Metric and Imperial units with precision.

The world uses two main measurement systems: the Metric System (used by most countries) and the Imperial/US Customary System (used primarily in the United States). This division creates daily challenges—from understanding weather forecasts abroad to buying groceries in a new country. Our converter eliminates the guesswork with exact mathematical conversions.

Temperature conversion deserves special attention because it's not a simple ratio—it involves both multiplication and an offset. Water freezes at 0°C (32°F) and boils at 100°C (212°F). This 100-degree Celsius range equals 180 Fahrenheit degrees, giving us the 5/9 and 9/5 conversion factors, plus the 32-degree offset.

Essential Conversion Formulas

Length: feet = meters × 3.28084 | meters = feet ÷ 3.28084
Weight: pounds = kilograms × 2.20462 | kilograms = pounds ÷ 2.20462
Temperature: °F = (°C × 9/5) + 32 | °C = (°F - 32) × 5/9

Quick Reference Conversion Table

MetricImperial/USCommon Use
1 meter3.28 feet / 39.4 inchesRoom dimensions
1 kilometer0.62 milesRoad distances
1 kilogram2.2 poundsBody weight, groceries
1 liter0.26 gallons / 33.8 ozBeverages, fuel
0°C32°FFreezing point
20°C68°FRoom temperature
37°C98.6°FBody temperature

Practical Examples

  • Running: A 5K race = 5 km = 3.1 miles. A 10K = 6.2 miles. A marathon = 42.195 km = 26.2 miles
  • Cooking: 180°C oven = 356°F ≈ 350°F setting. 200g flour ≈ 7 oz ≈ 1.5 cups
  • Travel: 100 km/h speed limit = 62 mph. 25°C weather = 77°F (pleasant!)
  • Fitness: 70 kg person = 154 lbs. 180 cm tall = 5'11"

Pro Tips for Unit Conversion

  • Quick mental math: 1 kg ≈ 2.2 lbs, so multiply kg by 2 and add 10%
  • For Celsius to Fahrenheit: double it and add 30 (approximate but fast)
  • Remember "a meter is a little more than a yard" and "a liter is a little more than a quart"
  • -40 is the same in both Celsius and Fahrenheit—a fun trivia fact!

Scenario Comparison

ScenarioMetric ValueImperial ValueCommon Use
Running a 10K race10 km6.21 milesRace distance planning
Cooking at 180°C180°C356°FOven temperature
Body weight 70kg70 kg154 lbsFitness tracking
Room 20 sq meters20 m²215 sq ftReal estate listing

Common Mistakes to Avoid

  • Forgetting temperature offset: °F = (°C × 9/5) + 32. The "+32" is crucial—don't just multiply! 20°C = 68°F, not 36°F.
  • Confusing fluid ounces with weight ounces: 1 fl oz of water ≈ 1 oz weight, but this varies by liquid density. Use the correct ounce type.
  • Mixing up miles and nautical miles: 1 nautical mile = 1.15 statute miles. Critical for aviation and maritime calculations.
  • Rounding too early: Convert first, then round the final answer. Rounding intermediate steps compounds errors.

Reference Standards

Measurement TypeSI Base UnitImperial Equivalent
Length1 meter (m)3.281 feet / 39.37 inches
Mass1 kilogram (kg)2.205 pounds
Volume1 liter (L)0.264 US gallons / 33.81 fl oz
TemperatureCelsius (°C)Fahrenheit: (°C × 9/5) + 32

When to Use This vs Others

  • This calculator: Best for converting between metric and imperial units for length, weight, temperature, and volume.
  • Scientific Calculator: Use for mathematical operations like trigonometry, logarithms, and exponents.
  • Time Zone Calculator: Use for time conversions across different time zones, not unit conversions.
  • Percentage Calculator: Use for percentage calculations, not physical unit conversions.

Related tools: Scientific Calculator for advanced math, Time Zone Calculator for international coordination, and Percentage Calculator for ratio calculations.

Frequently Asked Questions

How is unit conversion calculated?

Multiply by conversion factor. Length: 1 meter = 3.28 feet. Weight: 1 kg = 2.2 lbs. Temperature: °F = (°C × 9/5) + 32. Memorize common factors.

How to convert Celsius to Fahrenheit?

°F = (°C × 9/5) + 32. Quick estimate: double Celsius and add 30. Examples: 20°C = 68°F, 30°C = 86°F, 37°C = 98.6°F (body temp).

How many feet are in a meter?

1 meter = 3.28084 feet (or ~3 ft 3.4 in). Quick estimate: multiply meters by 3.3. A meter is slightly longer than a yard (3 feet exactly).