Does the order of bands matter?
Yes—start from the end closest to the tolerance band (often gold or silver). Enter the colors in that order so the decoded resistance matches the physical part.
Step-by-step walkthrough
Resistor Color Code Calculator Guide
Use this companion guide beside the interactive calculator to make sure you understand the “why” behind every click. Each section includes the classroom explanation, student-friendly language, and quick practice prompts.
Before you start
Collect the data points listed below and double-check their units. Keeping an organized “givens” list is one of the fastest ways to reduce math errors and impress exam graders.
- resistor color code
- resistance
- tolerance
Detailed procedure
Step 1
Choose whether the resistor uses 4- or 5-band markings.
Step 2
Select each band color from the palettes provided.
Step 3
Read the resistance in ohms, tolerance range, and ppm/°C if present.
Teaching & troubleshooting tips
Can I enter custom color sets?
The palette follows IEC standards. Extend the lookup tables inside the component if you need rare colors.