Convert between the metric and imperial systems instantly. Whether you need to convert centimetres to inches, feet to metres, or kilometres to miles, our fast, accurate tools have you covered.
All converters are free, require no sign-up, and work instantly in your browser. Simply enter a value, and the result updates as you type. Swap units with a single click.
The metric system uses centimetres, metres, and kilometres. The imperial system uses inches, feet, and miles. Most of the world uses metric, but the United States, United Kingdom, and a few other countries use imperial measurements.
Understanding the relationship between these units is essential for international work, travel, online shopping, and construction. The conversion factor between metric and imperial is fixed: 1 inch = exactly 2.54 centimetres (defined since 1959).
Our converters handle all common length conversions instantly and accurately. Whether you're measuring a room, converting a height, or calculating a distance, you can rely on these tools.
Some reference points to help you understand metric and imperial lengths:
1 centimetre equals 0.393701 inches, or about 3/8 of an inch. Since 1 inch = 2.54 cm exactly, we divide: 1 ÷ 2.54 = 0.393701 inches per cm.
1 foot = 30.48 centimetres exactly. This comes from the definition: 1 foot = 12 inches, and 1 inch = 2.54 cm, so 12 × 2.54 = 30.48 cm.
1 mile = 1.60934 kilometres. Conversely, 1 kilometre = 0.621371 miles. These are exact conversions used internationally.
Most countries adopted the metric system (introduced in France, 1799) for its simplicity and international standardization. The US, UK, and a few others retained imperial units for historical reasons, though even they use metric in science and commerce.
Yes, completely free. No sign up, no account, no limits. Just open and convert.