Scientific Notation API
Scientific number representation as an API. The scientific endpoint expresses a number in both scientific notation (one digit before the decimal point × a power of ten) and engineering notation (the exponent a multiple of three, lining up with SI prefixes), and reports the mantissa and exponent. The sigfigs endpoint rounds a number to a chosen number of significant figures, and counts the significant figures in a value — respecting the rules for leading zeros, trailing zeros and the decimal point, and flagging the ambiguous cases such as "1200". The si-prefix endpoint formats a number with the right metric prefix (1500 → 1.5 k, 2.3×10⁹ → 2.3 G, 0.0023 → 2.3 m) with an optional unit, and parses a prefixed value back to a plain number (2.2 MΩ → 2,200,000). Everything is computed locally and deterministically, so it is instant and private. Ideal for science and engineering tools, lab and measurement software, electronics and signal work, and education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 4 endpoints. This is scientific number representation; for locale number formatting use a number-format API and for number-to-words or Roman numerals use a number API.
api.oanor.com/sigfig-api
