The most effective resistor color code saying to memorize the digit sequence (0-9) is "Bad Beer Rots Our Young Guts But Vodka Goes Well" (Black, Brown, Red, Orange, Yellow, Green, Blue, Violet, Gray, White). Unlike building wire, which changes drastically by country, through-hole resistors universally follow the IEC 60062 standard. Below is the complete reference table, followed by bench-tested advice for reading faded components and avoiding common misidentifications.
The IEC 60062 Resistor Color Code Reference Table
This table applies to all standard 4-band, 5-band, and 6-band through-hole resistors globally. Read the bands from left to right, keeping the tolerance band (usually Gold or Silver) on the right.
| Color | Digit (Bands 1, 2, 3) | Multiplier (Band 4) | Tolerance (Band 5) | Temp Coefficient (Band 6) |
|---|---|---|---|---|
| Black | 0 | ×1 Ω | — | 250 ppm/°C |
| Brown | 1 | ×10 Ω | ±1% (F) | 100 ppm/°C |
| Red | 2 | ×100 Ω | ±2% (G) | 50 ppm/°C |
| Orange | 3 | ×1 kΩ | — | 15 ppm/°C |
| Yellow | 4 | ×10 kΩ | — | 25 ppm/°C |
| Green | 5 | ×100 kΩ | ±0.5% (D) | — |
| Blue | 6 | ×1 MΩ | ±0.25% (C) | 10 ppm/°C |
| Violet | 7 | ×10 MΩ | ±0.1% (B) | 5 ppm/°C |
| Gray | 8 | ×100 MΩ | ±0.05% (A) | — |
| White | 9 | ×1 GΩ | — | — |
| Gold | — | ×0.1 Ω | ±5% (J) | — |
| Silver | — | ×0.01 Ω | ±10% (K) | — |
Worked Example: A 4-band resistor with Yellow, Violet, Red, Gold bands. Yellow is 4, Violet is 7, Red is ×100 (two zeros). The value is 4,700 Ω (4.7 kΩ) with a ±5% tolerance.
Memorization: Choosing Your Resistor Color Code Saying
Mnemonics map the first letter of each word to the first letter of the color sequence. The sequence is always ordered by the visible light spectrum's frequency (lowest to highest energy), which is why Black (absence of light) is 0 and White (all light) is 9.
- The Classic (Most Popular): "Bad Beer Rots Our Young Guts But Vodka Goes Well." (Black, Brown, Red, Orange, Yellow, Green, Blue, Violet, Gray, White). This is the standard taught in most US and UK university labs.
- The Family-Friendly Alternative: "Better Be Ready Or Your Great Big Venture Goes West."
- The UK Engineering Variant: "Black Boys Run Over Your Garden But Violets Grow Wild."
What each row means in practice: The digit rows (Bands 1-3) give you the significant figures. The multiplier row (Band 4) tells you how many zeros to append, or in the case of Gold/Silver, where to place the decimal point. The tolerance row (Band 5) dictates the manufacturing variance. A 1 kΩ resistor with a Gold (5%) band could legally measure anywhere from 950 Ω to 1,050 Ω straight out of the package.
Rows People Get Wrong & Reading Faded Markings
Even with a good resistor color code saying memorized, physical components degrade. Here are the specific rows and colors that cause bench errors, and how to handle them.
The Most Misread Color Pairs
- Red (2) vs. Orange (3): Under warm 2700K LED or incandescent bench lighting, orange bands frequently look red. Fix: Take the resistor to a window with natural daylight (5000K+).
- Violet (7) vs. Gray (8): On older carbon composition resistors, violet fades to a muddy gray. If you are trying to distinguish between a 7 and an 8, look at the adjacent bands for context clues based on standard E12/E24 values.
- Gold vs. Yellow: Yellow is a digit (4); Gold is a multiplier (×0.1) or tolerance (5%). Gold always has a distinct metallic sheen and is usually spaced slightly further apart from the digit bands.
Safe Interpretation of Faded or Burnt Markings
If a resistor has been subjected to thermal stress, the bands may be completely illegible. Never guess the value based on circuit position alone.
If you measure a faded resistor while it is still soldered into the PCB, your multimeter will read the parallel equivalent resistance of the entire surrounding circuit. The reading will almost always be lower than the actual resistor value.
The Correct Procedure:
- De-energize the board and discharge all capacitors.
- Desolder one leg of the resistor and lift it away from the PCB pad.
- Measure across the legs with your DMM.
- Diagnostic Rule: If your in-circuit measurement is higher than the color code suggests, the resistor has suffered thermal drift or internal carbon tracking and must be replaced. Resistors rarely drift lower in value unless they are wirewound and shorting internally.
Component Codes vs. Regional Wiring Standards (NEC, IEC, UK)
A common point of confusion for DIYers transitioning from home wiring to electronics is assuming that color codes are universal across all electrical disciplines. They are not. While resistors strictly follow the global IEC 60062 standard, wire insulation colors vary wildly by region and governing body.
Do not apply your resistor color code saying to mains wiring. Use the reference table below to avoid lethal cross-wiring mistakes when integrating low-voltage control circuits with mains-powered enclosures.
| Function | US (NEC / NFPA 70) | EU / Global (IEC 60446) | Old UK (Pre-2004) |
|---|---|---|---|
| Protective Earth / Ground | Green, Green/Yellow, or Bare | Green/Yellow | Green |
| Neutral | White or Gray | Blue | Black |
| Line / Phase 1 (Hot) | Black (or Red/Blue for 240V) | Brown | Red |
| Line / Phase 2 | Red | Black | Yellow |
Key Takeaway: If you are building an ESP32 or Arduino project that switches a 120V/230V relay, the wires connecting your GPIO pins to the relay coil follow electronics conventions (usually Red for VCC, Black for GND). However, the wires connecting the relay's Common/NO terminals to your mains load must follow your local electrical code (NEC in the US, IEC in the EU). Always verify local AHJ (Authority Having Jurisdiction) requirements before terminating mains voltage.
For further reading on standard component markings, refer to the All About Circuits reference guide or the official IEC 60062 standard documentation.
