INTRODUCTION

The Resistor Code Calculator is used to decode the coloured bands on a resistor. By matching the band colours to a standard electronic code, it determines the component’s resistance value (in ohms), multiplier, and tolerance (accuracy), replacing manual look-up charts. This calculator should work in any modern browser, and, as with all the tools I have developed for pickledlightproject.com, the Resistor Code Calculator works entirely within your browser, uploading nothing to the server.

INSTRUCTIONS

To use the Resistor Code Calculator, you simply match the colours on the physical resistor to the dropdown menus in the tool:

1. Orient the Resistor: hold the resistor so the band closest to an end is on the left. Usually, the “tolerance” band (often gold or silver) is slightly wider or separated by a larger gap and should be on the right.
2. Select the Number of Bands: choose whether your resistor has 4 or 5 bands (this version of the calculator is restricted to those two options).
3. Input Colours: starting from the left, select the colour of each band in the calculator
• Bands 1 and 2 (and 3 on 5-band resistors) represent the Significant digits.
• The Multiplier band tells you how many zeros to add to those digits.
• The Tolerance Band indicates the precision (e.g. ±5%).
4. Read the Result: the calculator instantly converts these colours into a numerical value in Ohms (Ω), and simplifies large values into Kilohms (kΩ) or Megohms (MΩ).