Convert Inch (in) to Microinch (µin) instantly.
About these units
Inch (in)
An inch is defined as exactly 25.4 millimeters, a precise metric-based definition that preserves its usefulness within imperial systems. Historically, the inch was based on the width of three barleycorns placed end-to-end, a charming relic of medieval measurement practices. Today, the inch is vital in manufacturing, woodworking, consumer electronics (e.g., screen sizes), and tooling standards across the US and partially in the UK. Its size is small enough to offer usable precision yet large enough to avoid unwieldy fractions for many everyday objects. Even in predominantly metric industries, certain products—such as plumbing parts, bicycle rims, and camera mounts—retain inch-based standards for compatibility. This persistence shows how technological ecosystems can outlive their measurement origins.
Microinch (µin)
A microinch is one-millionth of an inch, approximately 2.54 × 10⁻⁸ meters. It is a precision unit used primarily in engineering, machining, and electronics. Microinches allow engineers to describe tolerances, surface roughness, and component dimensions with extreme accuracy. This is especially relevant in semiconductor manufacturing and microelectronics, where deviations of just a few microinches can impact performance. Although rarely encountered outside technical fields, the microinch demonstrates the need for highly granular units in modern technology, bridging the gap between traditional inches and nanometer-scale measurements.