Convert Microinch (µin) to Femtometer (fm) instantly.
About these units
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.
Femtometer (fm)
A femtometer, equal to 10⁻¹⁵ meters, is the scale at which the structure of atomic nuclei becomes measurable. Also known historically as a "fermi," this unit is used extensively in nuclear physics to describe the radii of protons, neutrons, and nuclei, which typically span 1–10 femtometers. At this scale, the strong nuclear force dominates interactions, and classical intuition breaks down almost entirely—quantum mechanics provides the only meaningful framework. The femtometer also plays a role in high-energy particle experiments, where the wavelengths of probing particles (like high-velocity electrons) may be expressed in femtometer increments. These small wavelengths allow researchers to resolve sub-nuclear structures. While invisible to any optical instrument, distances in the femtometer range can be inferred through scattering experiments, such as those performed in particle accelerators.