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Unit Converter
Length, Weight, Temperature & More

Our free unit converter handles 9 categories: length, weight, temperature, speed, volume, area, cooking measurements, data storage, and pressure. Instant results, no sign-up, works on any device.

Last updated: May 10, 2026

9 Categories

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Unit Converter

Formula —

Live Conversion

Conversion Summary

Select a category and enter a value to convert instantly.

Quick Reference

1 km=0.6214 mi

5 km=3.107 mi

10 km=6.214 mi

42.195 km=26.219 mi

Conversion Formulas & Reference

The exact conversion factors used by this tool, organized by category:

Length

km → miles: × 0.621371 | 100 km = 62.14 mi
miles → km: × 1.60934 | 26.2 mi (marathon) = 42.2 km
meters → feet: × 3.28084 | 1.8 m = 5 ft 11 in
cm → inches: × 0.393701 | 30 cm = 11.81 in

Weight

kg → lbs: × 2.20462 | 70 kg = 154.32 lbs
lbs → kg: × 0.453592 | 150 lbs = 68.04 kg
g → oz: × 0.035274 | 100 g = 3.53 oz
stone → lbs: × 14 | 10 stone = 140 lbs

Temperature

°C → °F: (°C × 9/5) + 32 | 0°C = 32°F • 37°C = 98.6°F • 100°C = 212°F
°F → °C: (°F − 32) × 5/9 | 72°F = 22.2°C
°C → K: °C + 273.15 | 0°C = 273.15 K (absolute zero = −273.15°C)

Speed

km/h → mph: × 0.621371 | 100 km/h = 62.14 mph
mph → km/h: × 1.60934 | 60 mph = 96.56 km/h
knots → mph: × 1.15078 | used in aviation and maritime
m/s → mph: × 2.23694 | 9 m/s = 20.13 mph (sprinting speed)

Volume

Liters → US gallons: × 0.264172 | 40 L = 10.57 gal — Note: UK gallon = 4.546 L, US gallon = 3.785 L
mL → fl oz: × 0.033814 | 250 mL = 8.45 fl oz
Cups → mL: × 236.588 | 1 cup = 236.6 mL (US standard)

Area

m² → ft²: × 10.7639 | 100 m² = 1,076 ft²
acres → m²: × 4046.86 | 1 acre = 4,047 m² (about the size of a football field)
hectares → acres: × 2.47105 | 1 ha = 2.47 acres

Cooking Measurements

1 tablespoon = 14.787 mL | 1 teaspoon = 4.929 mL
1 cup = 16 tablespoons = 48 teaspoons = 8 fl oz = 236.6 mL
Common mistake: UK tablespoon = 15 mL vs US tablespoon = 14.79 mL (negligible for cooking, but precise for chemistry).

Data Storage

1 GB = 1,024 MB = 1,048,576 KB (binary) | Manufacturers often use 1 GB = 1,000 MB (decimal), which is why a “1 TB” drive shows as ~931 GB in your OS.
1 TB = 1,024 GB (binary) | 1 MB = 1,024 KB

Pressure

PSI → kPa: × 6.89476 | 35 PSI (typical tire) = 241.3 kPa
Bar → PSI: × 14.5038 | standard car tire: 2.4 bar = 34.8 PSI
1 atm = 14.696 PSI = 101.325 kPa = 1.01325 bar (standard atmospheric pressure)

Real-World Reference Points by Category

Value	What it means
37°C / 98.6°F	Normal human body temperature
100 km/h / 62.1 mph	Standard highway speed limit (many countries)
32–35 PSI / 220–241 kPa	Typical passenger car tire inflation
1 cup / 236.6 mL	Standard US recipe measurement
1 TB / 1,024 GB	Storage capacity of a typical external hard drive
1 acre / 43,560 ft²	Approximately the size of an American football field

Related Tools

Fuel Cost Calculator — Uses miles and MPG; convert km/liters first if planning an international road trip.
Tip Calculator — Useful alongside unit conversions for international travel.
Discount Calculator — Great for international shopping where unit differences matter.
Percentage Calculator — Calculate percentage differences between measurements.

Frequently Asked Questions

How many miles is 1 kilometer?

1 kilometer = 0.621371 miles. As a quick rule of thumb, multiply km by 0.6 for a rough miles estimate. For more precision, use our converter above or the exact factor of 0.621371.

How do I convert Celsius to Fahrenheit?

Formula: °F = (°C × 9/5) + 32. Example: 25°C = (25 × 1.8) + 32 = 45 + 32 = 77°F. Quick estimate: double the Celsius temperature and add 30 (not precise but useful mentally). For example: 20°C → 20×2+30 = 70°F (actual: 68°F).

How many pounds is 1 kilogram?

1 kilogram = 2.20462 pounds. Roughly 2.2 lbs per kg. To convert quickly in your head: multiply kg by 2, then add 10%. Example: 70 kg → 70 × 2 = 140, + 7 = 147 lbs (actual: 154.3 lbs — this approximation is less accurate for large values; use the calculator for precision).

What is 100°F in Celsius?

°C = (100 − 32) × 5/9 = 68 × 5/9 = 37.78°C. Note: 98.6°F (normal body temperature) = exactly 37°C. 100°C is the boiling point of water = 212°F.

How many km is a 5K race?

A 5K race is exactly 5 kilometers, which equals approximately 3.107 miles. A 10K is 10 km = 6.214 miles. A half marathon is 21.097 km = 13.109 miles. A full marathon is 42.195 km = 26.219 miles.

How fast is 100 km/h in mph?

100 km/h = 62.14 mph. A quick mental rule: multiply km/h by 0.6 for a rough mph estimate. Common reference: 60 mph = 96.56 km/h (a standard US highway speed). 110 km/h = 68.35 mph. 130 km/h (European motorway) = 80.78 mph.

How many mL is 1 cup?

1 US cup = 236.588 mL. 1 cup = 8 fl oz = 16 tablespoons = 48 teaspoons. Note: a "metric cup" used in Australia and Canada = 250 mL. A British cup is also 250 mL. Always check the recipe origin to use the correct conversion.

Why does my 1 TB hard drive show 931 GB?

Drive manufacturers market using decimal units (1 TB = 1,000,000,000,000 bytes), but operating systems measure in binary units (1 GB = 1,073,741,824 bytes). So 1 TB (decimal) ÷ 1.0737 = 931.32 GB (binary). This is not a defect — it's simply a difference in how the units are defined.

What PSI should my car tires be?

Most passenger cars recommend 30–35 PSI (207–241 kPa or 2.1–2.4 bar). The exact recommended pressure is on the sticker inside your driver's door or in the owner's manual — not on the tire sidewall (that shows the maximum pressure). Check when tires are cold for the most accurate reading.

How many square feet is 1 acre?

1 acre = 43,560 square feet = 4,047 m² = 0.4047 hectares. A standard American football field (including end zones) is about 1.32 acres. A 1/4-acre residential lot is approximately 10,890 ft².

⚠️ Disclaimer: Conversion factors are standard internationally recognized values. For scientific or engineering applications, verify with your institution's standards. See our full Disclaimer.

Unit Converter Length, Weight, Temperature & More