Resistor Color Code Calculator — Decode 4 & 5 Band Resistors
The resistor color code is a standardized system for marking resistance values using colored bands. Select the colors on your resistor to instantly decode its value. For a 4-band resistor, the first two bands are digits, the third is the multiplier (power of 10), and the fourth is tolerance. 5-band precision resistors add a third digit for higher accuracy.
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Frequently Asked Questions
How do I read a resistor color code?
Hold the resistor so the tolerance band (Gold or Silver) is on the right. Read the colored bands from left to right. For a 4-band resistor: the first two bands are digits, the third is the multiplier, and the fourth is tolerance. Multiply the two-digit number by the multiplier to get the resistance in ohms.
What do the colors mean on a resistor?
Each color represents a number: Black=0, Brown=1, Red=2, Orange=3, Yellow=4, Green=5, Blue=6, Violet=7, Gray=8, White=9. Gold and Silver are only used as multipliers (×0.1, ×0.01) or tolerance bands (±5%, ±10%). A useful mnemonic is: Bad Boys Race Our Young Girls But Violet Generally Wins.
What is the difference between a 4-band and 5-band resistor?
A 4-band resistor uses two digit bands + multiplier + tolerance, giving 2 significant figures. A 5-band resistor uses three digit bands + multiplier + tolerance, giving 3 significant figures. 5-band resistors are precision resistors with tighter tolerances (typically ±1% or better), used in high-accuracy circuits.
What does the Gold band mean on a resistor?
When Gold is the last band (tolerance position), it means the resistor has ±5% tolerance — the most common tolerance for general-purpose resistors. When Gold appears as the multiplier band (3rd or 4th position in a 4-band or 5-band scheme), it means ×0.1, used for fractional ohm values like 4.7 Ω.
How accurate is a ±5% resistor?
A ±5% resistor can deviate up to 5% from its stated value. For example, a 100 Ω ±5% resistor can measure anywhere between 95 Ω and 105 Ω. For most digital circuits and LED drivers this is perfectly acceptable. For precision analog circuits, op-amp feedback networks, or measurement circuits, use ±1% (Brown tolerance band) or better.
What are E24 and E96 resistor series?
E-series are standardized sets of resistor values per decade. E24 has 24 values per decade (e.g., 100, 110, 120...910 Ω) and corresponds to ±5% tolerance. E96 has 96 values per decade for ±1% precision resistors. E12 has 12 values for ±10% parts. Most hobbyist kits include E24 values; precision work uses E96.
How do I identify which end of a resistor to start reading?
Start from the end closest to a band (i.e., the end where the first band is nearest to the lead). The tolerance band (Gold, Silver, or Brown for precision types) is typically wider or spaced further from the other bands, and is always the last band. If in doubt, read both ways and choose the value that matches a standard E-series value.
What is a 0 ohm resistor used for?
A 0 Ω resistor (single Black band) is a wire link in component form. It is used to bridge tracks on a single-sided PCB, select configurations via jumper, or act as a zero-resistance placeholder during prototyping. They are packaged like regular resistors so they can be placed by automated pick-and-place machines.
Resistor Color Code Chart
The resistor color code is a standardized system (IEC 60062) for marking the resistance value, tolerance, and sometimes the temperature coefficient of resistors using colored bands painted on the component body. Each color corresponds to a digit, a multiplier, and optionally a tolerance percentage.
| Color | Digit Value | Multiplier | Tolerance |
|---|---|---|---|
| Black | 0 | ×1 | — |
| Brown | 1 | ×10 | ±1% |
| Red | 2 | ×100 | ±2% |
| Orange | 3 | ×1k | ±3% |
| Yellow | 4 | ×10k | ±4% |
| Green | 5 | ×100k | ±0.5% |
| Blue | 6 | ×1M | ±0.25% |
| Violet | 7 | ×10M | ±0.1% |
| Gray | 8 | ×100M | ±0.05% |
| White | 9 | ×1G | — |
| Gold | — | ×0.1 | ±5% |
| Silver | — | ×0.01 | ±10% |
How to Read a 4-Band Resistor
A 4-band resistor has three value bands and one tolerance band. Hold the resistor so the tolerance band (Gold or Silver) is on the right. Read left to right:
Formula
Resistance = (Digit1 × 10 + Digit2) × Multiplier
Example: Yellow–Violet–Brown–Gold
Yellow = 4, Violet = 7, Brown = ×10, Gold = ±5%
Resistance = (4 × 10 + 7) × 10 = 470 Ω ±5%
- Band 1 — First significant digit (0–9)
- Band 2 — Second significant digit (0–9)
- Band 3 — Multiplier (×1 to ×1G, or ×0.1, ×0.01)
- Band 4 — Tolerance (Gold ±5%, Silver ±10%, Brown ±1%, etc.)
How to Read a 5-Band Resistor
5-band resistors are used for precision resistors (1% and better). They add a third digit band for greater resolution. The tolerance band is still the last band.
Formula
Resistance = (Digit1 × 100 + Digit2 × 10 + Digit3) × Multiplier
Example: Brown–Black–Black–Brown–Brown
Brown = 1, Black = 0, Black = 0, Brown = ×10, Brown = ±1%
Resistance = (1 × 100 + 0 × 10 + 0) × 10 = 1000 Ω = 1 kΩ ±1%
- Band 1 — First significant digit (0–9)
- Band 2 — Second significant digit (0–9)
- Band 3 — Third significant digit (0–9)
- Band 4 — Multiplier
- Band 5 — Tolerance
Tolerance Explained
Tolerance specifies the maximum deviation from the stated resistance value. A 470 Ω ±5% resistor can measure anywhere from 446.5 Ω to 493.5 Ω and still be within specification.
| Color | Tolerance | Series |
|---|---|---|
| Brown | ±1% | E96 |
| Red | ±2% | E48 |
| Orange | ±3% | E24 |
| Yellow | ±4% | E24 |
| Green | ±0.5% | E192 |
| Blue | ±0.25% | E192 |
| Violet | ±0.1% | E192 |
| Gray | ±0.05% | E192 |
| Gold | ±5% | E24 |
| Silver | ±10% | E12 |
For critical circuits, use ±1% (Brown) or better. For general purpose work, ±5% (Gold) is fine.
E24 and E96 Standard Values
Resistors are manufactured in standardized values called E-series. The number indicates how many values exist per decade. E24 (24 values, ±5%) is the most common for general use; E96 (96 values, ±1%) is used for precision applications.
E24 Base Values (×1 to ×10 MΩ)
1.0, 1.1, 1.2, 1.3, 1.5, 1.6, 1.8, 2.0, 2.2, 2.4, 2.7, 3.0, 3.3, 3.6, 3.9, 4.3, 4.7, 5.1, 5.6, 6.2, 6.8, 7.5, 8.2, 9.1
× any power of 10 (1 Ω, 10 Ω, 100 Ω, 1 kΩ, 10 kΩ, 100 kΩ, 1 MΩ...)
E12 Base Values (±10%)
1.0, 1.2, 1.5, 1.8, 2.2, 2.7, 3.3, 3.9, 4.7, 5.6, 6.8, 8.2
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