Resistance Calculator
This calculator will convert the colour codes to resistance values and calculate the overall serial or parallel circuit resistance.
What Is Resistance?
Something that forces the electric current not to flow is known as the resistance.
How To Calculate Resistance?
Following are the standard voltage current resistance formulas to measure resistance:
Colour Codes:
Colour codes correspond to the ratings that define the potential of certain electrical components. But we have considered the codes for resistances only.
- Hold the resistance in your hand with tolerance bands to the most right
- Start noticing bands one by one from left to right and pick a value from the table (against colour) to estimate the desired ohm value.
For instance, the following pictures will let you understand pattern to calculate ohm value that you are holding:
3 Band Resistor:
4 Band Resistor:
5 Band Resistor:
6 Band Resistor:
Our electrical resistance calculator takes into account the table below to decode the colour code into value:
| Color | 1st, 2nd, 3rd Band Significant Figures | Multiplier | Tolerance | Temperature Coefficient |
|---|---|---|---|---|
| Black | 0 | × 1 | 250 ppm/K (U) | |
| Brown | 1 | × 10 | ±1% (F) | 100 ppm/K (S) |
| Red | 2 | × 100 | ±2% (G) | 50 ppm/K (R) |
| Orange | 3 | × 1K | ±0.05% (W) | 15 ppm/K (P) |
| Yellow | 4 | × 10K | ±0.02% (P) | 25 ppm/K (Q) |
| Green | 5 | × 100K | ±0.5% (D) | 20 ppm/K (Z) |
| Blue | 6 | × 1M | ±0.25% (C) | 10 ppm/K (Z) |
| Violet | 7 | × 10M | ±0.1% (B) | 5 ppm/K (M) |
| Grey | 8 | × 100M | ±0.01% (L) | 1 ppm/K (K) |
| White | 9 | × 1G | ||
| Gold | × 0.1 | ±5% (J) | ||
| Silver | × 0.01 | ±10% (K) | ||
| None | ±20% (M) |
Serial Resistance:
\(R_{total} = R_{1}+R_{2}+R_{3}+R_{4}+R_{5}+...+R_{n}\)
Parallel Resistance:
\(R_{total} = \dfrac{1}{\dfrac{1}{R_{1}}+\dfrac{1}{R_{2}}+\dfrac{1}{R_{3}}+\dfrac{1}{R_{4}}+\dfrac{1}{R_{5}}+...+\dfrac{1}{R_{n}}}\)
Conductor Resistance:
\(R = \dfrac{L}{A*C}\)
Where;
L = Length of Conductor
A = Cross Sectional Area of the Conductor
C = Material’s Conductivity
How Does Our Circuit Resistance Calculator Work?
Calculating resistance with our calculator is quite easy and swift. Let’s learn its usage!
Input:
- Please select the resistance method from the top list there on tool
- Once you are done with your choice, go by entering the values or selecting colour combinations for your resistances
- Hit the calculate button
Output:
- Resistance calculations for conductors and circuits
References:
From the source of Wikipedia: Electrical resistance and conductance, Ohm's law, Static and differential resistance, AC circuits, Energy dissipation and Joule heating From the source of Khan Academy: Current, do electrons in alternating current circuits From the source of Coursehero: Resistors, Temperature and Superconductivity, Resistivity
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