Work out resistor value to colour code instantly with clear inputs, formula shown and shareable results.
Going from a value to bands means normalising to two significant digits and a power of ten: 4,700 becomes 4, 7 and a multiplier of 100, giving yellow-violet-red. The nearest E12 preferred value is shown too, because arbitrary values are not manufactured — only the E series steps are.
Value to code
Normalise to two digits x 10^n; digits give bands 1 and 2 and n gives the multiplier colour
Electrical results are planning estimates only. Verify against the applicable wiring rules (IEC 60364, BS 7671, NEC or local code) and have all installation work designed and checked by a qualified electrician.
Standard value sets spaced so that consecutive values differ by about their tolerance. E12 has 12 values per decade for 10% parts, E24 has 24 for 5% parts.
Because it is an E12 value. Nearly all through-hole resistors are made only in E12 or E24 steps, so designs converge on them.