Conduction, convection and Stefan-Boltzmann radiation in series and in parallel, solving for Q, thickness, k, h, emissivity or area. The series case iterates the radiation term at the unknown surface temperature instead of summing a resistance that is not constant, and air at 0.026 W/(m K) is in the table.
Pipe flow from ID and velocity, or solved from a pressure drop and length with an iterated Colebrook-White friction factor alongside the explicit Swamee-Jain and Haaland approximations and the gap between them. Separates laminar, transition and turbulent regimes and says where the equations stop being reliable.
Independent, paired and one-sample t-tests from real summary statistics: the t statistic, degrees of freedom, p-value and a verdict at alpha 0.05.
Push uncertainties through any formula step by step, in quadrature or worst case, with partial derivatives and a relative or absolute output error.
A real entropy estimate in bits from character-class pools with a repetition penalty, an estimated crack time, a common-password list check and a live verdict.
Batches of UUID v4 values from the browser's own CSPRNG, plus CRC32, FNV-1a and DJB2 of any text with both hex and decimal output.
An IPv4 CIDR into its network address, netmask, broadcast, total and usable host counts and the first and last usable host, with the address as a 32-bit integer and back.
Compare two semantic versions the way semver actually orders them, sort a list, and see what a caret or tilde range resolves to.
