Convert feet to mm

脚

定义
A foot (symbol: ft) is a traditional length unit in the Imperial and U.S. customary systems. Since 1959, it has been standardized as exactly 0.3048 meters. Each foot comprises 12 inches, and three feet make one yard.

历史与起源
Across ancient cultures—from Greek and Roman to medieval English and Chinese—the length of a “foot” varied widely (roughly 250 mm to 335 mm), often based on human body parts. To unify these disparate measures, an international agreement in 1959 fixed the foot at 0.3048 m.

现代使用
Feet are still the primary unit for everyday measurements in the United States, Canada, and the United Kingdom. You’ll encounter feet when measuring personal height, room dimensions, sports fields, and aviation altitudes.

毫米

定义
A millimeter (symbol: mm) is an SI-derived unit of length equal to one-thousandth of a meter (0.001 m). It corresponds to the distance light travels in 1⁄299 792 458 000 of a second.

历史与起源
前缀 毫 （拉丁语 密尔, “thousand”) denotes a factor of 10⁻³. While the meter’s realization has evolved—from a physical prototype bar to a light-based constant—the link 1 mm = 0.001 m has remained constant.

现代使用
Millimeters are crucial for high-precision tasks: engineering tolerances, technical drawings, machining parts, and any application where sub-centimeter accuracy is required.

Foot → Millimeter Conversion Table

如何转换

• 1 ft = 304.8 mm

• 1 mm ≈ 0.00328084 ft

示例

Convert 15 ft to millimeters:

15 ft × 304.8 mm/ft = 4572 mm