Convert Thou to Micrometers

Convert Thou (th) to Micrometers (μm) instantly and accurately.

Conversion Formula

μm = th × 25.4

About Thou

A thou (also called mil) is one thousandth of an inch, equal to 0.0254 millimeters or 25.4 micrometers. This unit is commonly used in engineering and manufacturing in countries that use imperial measurements, particularly for specifying tolerances, wire gauges, and thin material thicknesses. For example, a standard plastic bag might be 1-2 thou thick, a sheet of paper is about 4 thou, and precision machined parts often have tolerances measured in thou. Electronic circuit board copper traces are typically 1.4 thou thick.

About Micrometers

A micrometer (μm), also called a micron, is one millionth of a meter (10⁻⁶ m). This is the scale of bacteria, small cells, and fine particles. Most bacteria range from 1-10 micrometers in length, while human red blood cells are about 6-8 micrometers in diameter. The smallest particles visible to the naked eye are around 40 micrometers. This unit is essential in biology, medicine, and precision engineering, where measurements of microscopic structures and tolerances are critical.

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