Convert Span (Cloth) (span) to Angstrom (Å) instantly.
About these units
Span (Cloth) (span)
The span is a unit traditionally used in textile measurement, equal to the distance between the tip of the thumb and the tip of the little finger when the hand is fully extended, approximately 22.86 cm (9 inches). This anthropometric unit was widely used by weavers and cloth merchants to measure lengths of fabric quickly and intuitively. Its small scale made it convenient for practical applications where tape measures or rulers were unavailable. The span also appears in cultural and historical texts as a natural unit of human proportion. While largely obsolete today, it offers insight into pre-industrial textile practices and the anthropometric basis of early measurement systems.
Angstrom (Å)
The ångström, equal to 10⁻¹⁰ meters, is traditionally used to measure atomic scales, bond lengths, and wavelengths of electromagnetic radiation, particularly in the X-ray and ultraviolet regions. Although not an SI unit, the ångström persists because it aligns conveniently with many natural atomic dimensions — hydrogen's typical bond lengths, for example, are close to 1 Å. Scientists in crystallography, astronomy, materials science, and spectroscopy routinely use ångströms when describing the spacing between atoms in a crystal lattice or the wavelength of certain spectral lines. The convenience comes from avoiding unwieldy decimals: instead of writing 0.154 nm, one may write 1.54 Å. While modern research increasingly prefers SI nanometers or picometers, the ångström remains deeply embedded in scientific traditions and continues to serve as a practical shorthand for atomic-scale measurements.