Vishay through-hole resistors use the globally standardized IEC 60062 color code system. There is no proprietary "Vishay-only" color code; whether you are holding a Vishay PR02 flameproof resistor, an MRS25 precision metal film resistor, or a vintage Beyschlag component (acquired by Vishay), you decode the bands using the universal chart below. Read the bands from left to right, starting from the end with the band closest to the wire lead, leaving the wider-spaced tolerance band for the far right.
The Complete Vishay Resistor Color Code Reference Table
| Color | Digit (Bands 1-3) | Multiplier (Band 3 or 4) | Tolerance (Band 4 or 5) | TCR (Band 6, ppm/K) |
|---|---|---|---|---|
| Black | 0 | ×1 Ω | — | — |
| Brown | 1 | ×10 Ω | ±1% (F) | 100 |
| Red | 2 | ×100 Ω | ±2% (G) | 50 |
| Orange | 3 | ×1 kΩ | — | 15 |
| Yellow | 4 | ×10 kΩ | — | 25 |
| Green | 5 | ×100 kΩ | ±0.5% (D) | — |
| Blue | 6 | ×1 MΩ | ±0.25% (C) | 10 |
| Violet | 7 | ×10 MΩ | ±0.1% (B) | 5 |
| Grey | 8 | — | ±0.05% (A) | — |
| White | 9 | — | — | — |
| Gold | — | ×0.1 Ω | ±5% (J) | — |
| Silver | — | ×0.01 Ω | ±10% (K) | — |
Global Standards vs. Regional Wiring Codes
A common point of confusion for beginners crossing over from home electrical work to electronics is the assumption that component markings vary by country. They do not. While mains wiring colors vary drastically by region—for example, US NEC 310.12 uses black/red for hot conductors, IEC 60446 (Europe/Global) uses brown/black, and the old pre-2004 UK standard used red/black—resistor color codes are universally governed by IEC 60062.
When you buy a Vishay SFR25 or MRS25 series resistor from Mouser, Digi-Key, or a local supplier in Tokyo, London, or New York, the color bands mean the exact same thing. There is no "US variant" or "UK variant" of the Vishay resistor color code. The only regional difference you might encounter is the printed text on the packaging (e.g., EIA-96 SMD codes vs. through-hole color bands), but for leaded axial resistors, IEC 60062 is the absolute global law.
The "Rows People Get Wrong" Notes
- Red vs. Orange (The Heat Fade Problem): On older Vishay PR01 and PR02 flameproof resistors, the red pigment (Digit 2) frequently degrades into a muddy orange or brown when exposed to prolonged heat. If the second band looks like a "burnt orange," do not trust your eyes. Assume it is Red (2) if it is in the first two digit positions, but verify with a multimeter.
- Gold and Silver Placement: Gold and Silver can appear as either a multiplier or a tolerance band, but never as a primary digit. If you see a Gold band, it is either multiplying the value by 0.1 (e.g., Brown-Black-Gold-Gold = 1.0Ω ±5%) or it is the 5% tolerance band at the far right. The physical spacing is your clue: the tolerance band is usually separated by a wider gap from the multiplier band.
- 5-Band vs. 4-Band Reading Direction: Vishay’s precision MRS16 and MRS25 series use 5 bands (3 digits, 1 multiplier, 1 tolerance). Standard 5% carbon or metal film resistors use 4 bands (2 digits, 1 multiplier, 1 tolerance). If you try to read a 5-band 1% resistor as a 4-band 5% resistor, your value will be off by a factor of 10. Always count the total bands before assigning column values.
- The "Zero-Ohm" Jumper: A single black band in the center of a Vishay axial body is a 0Ω jumper wire, not a 0Ω resistor with a complex code. It is used for automated PCB insertion machines to place wire links.
Decision Path: Selecting the Right Vishay Series
Use this decision matrix to terminate your selection process and pick the exact Vishay part series you need for your BOM (Bill of Materials) based on your circuit’s physical and electrical demands.
| Condition / Requirement | Secondary Constraint | Concrete Pick (Vishay Series) |
|---|---|---|
| High voltage / Mains isolation required | Needs flameproof coating and failsafe open-circuit under overload | Vishay PR02 (Flameproof metal film, 2W, up to 500V) |
| Precision analog / ADC reference scaling | Requires ≤1% tolerance and tight temperature stability | Vishay MRS25 (Professional metal film, 0.6W, 1%, 50ppm/K) |
| General purpose pull-up/pull-down or LED limiting | Cost-sensitive, 5% tolerance acceptable, standard 1/4W or 1/6W | Vishay SFR25 (Standard metal film, 0.25W, 5%, 100ppm/K) |
| High pulse / Surge current environment | Must survive inrush currents without carbon composition noise | Vishay VR25 (High ohmic, pulse withstanding, up to 1600V) |
Safe Interpretation When Markings Are Faded or Burned
When a resistor has been subjected to thermal runaway, the paint body may turn entirely dark brown or black, obliterating the IEC 60062 color bands. Here is the exact bench procedure to safely determine the value and assess if the component is still viable.
- Isolate and De-energize: Remove all power from the board. Discharge any large electrolytic capacitors using a high-wattage bleeder resistor (e.g., 1kΩ 5W) to prevent your multimeter from being blown by stored voltage.
- Lift One Leg: Use a temperature-controlled soldering iron (set to 350°C for lead-free, 320°C for leaded) to desolder and lift just one leg of the suspect resistor from the PCB pad. This breaks any parallel circuit paths.
- Measure with a Bench DMM: Connect your multimeter probes directly to the resistor leads. For values under 10Ω, use the relative (REL) mode to zero out your test lead resistance (which is typically 0.2Ω to 0.5Ω for standard silicone leads).
- Calculate Parallel Drift (If you cannot lift the leg): If you absolutely must measure in-circuit, and you know the exact resistance of the parallel path ($R_p$), use the reverse parallel formula to find the actual resistor value ($R_x$):
R_x = (R_measured × R_p) / (R_p - R_measured)
Example: You measure 8.5kΩ in-circuit. You know there is a 100kΩ pull-down resistor in parallel.R_x = (8500 × 100000) / (100000 - 8500) = 9,289Ω. The burned resistor is likely a nominal 9.1kΩ or 10kΩ that has drifted. - Assess Physical Damage: If the multimeter reads "OL" (open loop) on a resistor that should be low-ohms, the internal film has vaporized. If the measured value has drifted more than 10% from its suspected nominal value (even if the color bands suggest a 5% tolerance), replace it. Vishay metal film resistors rarely drift slightly; they either stay in spec or fail open under severe thermal stress.
By relying on the universal IEC 60062 standard and verifying degraded components with proper isolation techniques, you eliminate guesswork from your troubleshooting and BOM sourcing. When in doubt, cross-reference the physical dimensions and power rating with the official Vishay resistor catalog to confirm the exact series before ordering replacements.
