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Calculator of magnetic field of straight round conductor

$$ H(d) = \frac{I_{tot}·r^2}{2·π·d·R^2} $$	(A/m)	Equations are valid inside as well as outside of the wire (with certain assumptions)	$$ B(d) = \frac{μ_r·μ_0·I_{tot}·r^2}{2·π·d·R^2} $$	(T)
Total current in wire I_tot (A) = Radius of wire R (mm) = Radius from centre d (mm) = Relative permeability of wire μ_r (unitless) = Relative permeability of surrounding medium μ_r (unitless) = H = (A/m) B =
Assumptions: current distribution is uniform, permeability is uniform and isotropic, high-frequency effects (radiation and relativistic) are negligibly small, where: $I_{tot}$ - total current (A) in the wire, $r$ - variable radius (m) within the wire from its centre such that $0 \leq r \leq R$ (and $r=d$ within the wire) , $d$ - any positive variable radius (m) from centre of wire, $R$ - outer radius (m) of the wire, $μ_r$ - relative permeability (unitless) of wire or the surrounding medium, and $μ_0$ = 4·π·10^-7 H/m is the permeability of vacuum .