Resistor Bands
Select 4-band (standard), 5-band (precision 1%), or 6-band (with tempco).
Relevant Draftsbook Lessons & Microprocessor Guides
Explore hardware concepts, bus architectures, and circuit interfacing in our structured courses:
Resistor Color Codes & Circuit Calculator Guide
Decode 4, 5, and 6-band resistors and solve Ohm’s Law and circuit power relationships offline.
Overview
The Resistor & Circuit Calculator decodes 4-band, 5-band, and 6-band standard and precision resistor color codes, displaying exact nominal resistance, tolerance bounds, and temperature coefficients alongside an interactive physical resistor preview. Additionally, it solves DC circuit relationships (Ohm’s Law V = I × R and Joule’s First Law P = V × I) given any two known circuit quantities, handling engineering prefixes (µ, m, k, M, G) and zero-denominator safeguards.
How to Calculate Circuit Quantities and Resistor Values
Select the Resistor Color Code Decoder tab or the Ohm’s Law & Power Calculator tab.
Choose 4, 5, or 6 bands and click the color pickers to match the physical resistor stripes.
Fill in any two fields (Voltage, Current, Resistance, or Power) and select your preferred engineering units.
Inspect tolerance ranges, formulas used, and check out connected microprocessor and hardware lessons.
- Steady-State DC Assumptions: Ohm’s Law calculations assume passive linear circuits in DC steady state. AC capacitive or inductive reactance is neglected.
- Zero-Denominator Protection: Open-circuit (zero current) and short-circuit (zero resistance) conditions are detected and labeled safely without arithmetic errors.
- Realistic Passive Values: Power and resistance cannot be negative in passive DC circuits.
- Local Execution: All circuit solving and resistor parsing occurs entirely inside client memory with zero server calls.
- Zero Data Stored: Values entered are not tracked or saved to persistent storage.