When you are digging through a mixed bin of through-hole components or repairing a legacy PCB, the 4 band resistor color code chart is your fastest path to identifying a part without desoldering it. The direct answer for the most common bench scenario: a resistor with Brown, Black, Red, and Gold bands is 1,000 ohms (1 kΩ) with a 5% tolerance.
This guide provides the complete, standard-compliant reference table, explains how to apply tolerance and power derating modifiers to your specific installation, and answers the most common long-tail questions we see from hobbyists and trade students.
The Complete 4 Band Resistor Color Code Chart (IEC 60062)
The following table is governed by the International Electrotechnical Commission (IEC) 60062 standard, which defines the marking codes for resistors and capacitors.
| Color | Digit Value (Bands 1 & 2) | Multiplier (Band 3) | Tolerance (Band 4) |
|---|---|---|---|
| Black | 0 | ×1 (10⁰) | — |
| Brown | 1 | ×10 (10¹) | ±1% (F) |
| Red | 2 | ×100 (10²) | ±2% (G) |
| Orange | 3 | ×1,000 (10³) | — |
| Yellow | 4 | ×10,000 (10⁴) | — |
| Green | 5 | ×100,000 (10⁵) | ±0.5% (D) |
| Blue | 6 | ×1,000,000 (10⁶) | ±0.25% (C) |
| Violet | 7 | ×10,000,000 (10⁷) | ±0.1% (B) |
| Gray | 8 | — | ±0.05% (A) |
| White | 9 | — | — |
| Gold | — | ×0.1 (10⁻¹) | ±5% (J) |
| Silver | — | ×0.01 (10⁻²) | ±10% (K) |
Bookmark-friendly quick-jump rows: The most queried values on the bench are Gold (5% tolerance, ×0.1 multiplier), Silver (10% tolerance, ×0.01 multiplier), and Red (×100 multiplier, 2% tolerance).
Which Column Applies to Your Circuit Installation
Not every column in the chart applies to every band. The physical position of the band on the resistor body dictates which column you must reference:
- Bands 1 and 2 (Significant Digits): Always use the Digit Value column. These bands will never be Gold or Silver, as those colors do not represent whole integer digits in the IEC 60062 standard.
- Band 3 (Multiplier): Use the Multiplier column. This tells you how many zeros to append to your first two digits (or where to place the decimal point if the band is Gold or Silver).
- Band 4 (Tolerance): Use the Tolerance column. This is almost always Gold (5%) for standard carbon film resistors or Brown/Red (1%/2%) for metal film precision resistors.
Installation context: If you are installing the resistor in a precision analog front-end (like an op-amp feedback loop or an ADC voltage divider), the Tolerance column is your deciding factor. A 5% (Gold) tolerance part will introduce unacceptable noise and offset errors; you must select a 1% (Brown) or 0.1% (Violet) metal film resistor for those specific nodes.
How Tolerance and Power Derating Modify the Base Value
A common mistake is assuming a 1,000 Ω resistor will measure exactly 1,000 Ω on your multimeter. The 4th band (tolerance) and the physical environment (power derating) modify the base value in real-world operation.
1. The Tolerance Modifier (Base Value Bounds)
The tolerance band establishes the absolute upper and lower bounds of the resistor's actual value. Electronics Tutorials notes that manufacturers sort resistors into these bins after production.
Worked Example: You have a 4.7 kΩ resistor (Yellow-Violet-Red-Gold).
Base value: 4,700 Ω.
Tolerance modifier: 5% of 4,700 = 235 Ω.
Actual acceptable range: 4,465 Ω to 4,935 Ω. If your multimeter reads 4.45 kΩ, the part is out of spec and likely damaged.
2. Power Derating (Temperature Modifier)
While the color code chart does not show power derating, the physical installation does. Resistors are typically rated for their nominal power (e.g., 1/4W) up to an ambient temperature of 70°C. Above 70°C, the manufacturer's derating curve requires you to linearly reduce the allowable power dissipation, hitting 0W at 155°C. If you ignore this derating modifier and push 0.25W through a 1/4W resistor in a 90°C enclosure, the resistance value will permanently drift upward, and the part will eventually fail open.
What the Color Code Chart Cannot Tell You
The IEC 60062 color code is strictly for identifying resistance and tolerance. It is completely blind to several critical parameters you must verify before installing a part:
- Power Rating (Wattage): A 100 Ω 1/8W resistor and a 100 Ω 2W resistor have the exact same color code (Brown-Black-Brown-Gold). You must determine wattage by physical size (e.g., a standard 1/4W resistor is roughly 6.3mm long, while a 1/2W is 9.2mm).
- Maximum Working Voltage: Even if a 1/4W resistor theoretically handles high voltage via Ohm's Law (V = √(P×R)), standard 1/4W resistors are typically limited to 250V maximum working voltage to prevent internal arcing.
- Composition and Parasitics: The chart won't tell you if the part is carbon composition (high inductance/capacitance, noisy) or metal film (low noise, stable). For high-frequency RF circuits, parasitic inductance matters more than the nominal resistance.
4 Band Resistor Color Code Chart FAQ
How do I know which end to start reading the 4 band resistor color code?
Look for the Gold or Silver band. Because Gold and Silver are never used as the first significant digit in the standard E12/E24 series, the tolerance band (Gold/Silver) is always placed on the far right. Hold the resistor so the Gold or Silver band is on the right, and read left to right. If the resistor has no Gold/Silver band (rare, usually 20% tolerance parts without a 4th band), read it so the resulting value matches a standard E12 or E24 preferred number (e.g., 47, 56, 68) rather than a non-standard number (like 76 or 83).
Why is there no white band in the standard 4 band resistor color code chart?
White is in the chart as Digit 9, but it is almost never used as a Multiplier or Tolerance band. You will see white as a first or second digit (e.g., White-Brown-Black = 91 Ω), but you will not see it as a 3rd or 4th band because a multiplier of 10⁹ (1 Giga-ohm) is practically nonexistent in standard through-hole kits, and white has no assigned tolerance letter in the IEC standard.
Can I use a 4 band resistor chart to read a 5 band resistor?
No. As SparkFun's resistor tutorial explains, 5-band resistors are used for higher precision (typically 1% or better) and include a third significant digit. In a 5-band resistor, Bands 1, 2, and 3 are digits, Band 4 is the multiplier, and Band 5 is the tolerance. If you apply the 4-band logic to a 5-band part, your calculated value will be off by an order of magnitude.
What happens if the 4 band resistor colors are faded or burnt?
If a resistor has overheated, the epoxy coating often turns dark brown or black, obscuring the bands. Do not guess. Desolder one leg of the resistor from the PCB to isolate it from parallel circuit paths, then measure it directly with a digital multimeter. If the part reads open (OL) or significantly outside its expected tolerance bounds, replace it with a new metal film part of the same value and equal or higher wattage.
