Unlike resistors, the base unit for all capacitor color codes is the picofarad (pF). When you use a capacitor colour code calculator or read the bands manually, a reading of '103' or Brown-Black-Orange means 10,000 pF (10 nF or 0.01 µF). This guide provides the definitive EIA RS-279 reference table, resolves regional standard conflicts, and gives you a concrete decision path for identifying, testing, and replacing legacy tubular and mica capacitors.
The Complete Capacitor Colour Code Reference Table
The following spec-sheet-table covers the standard 3-band, 4-band, and 5-band tubular ceramic and mica capacitor codes. Read bands from the top down or left to right, depending on the component orientation.
| Color | Band 1 (Digit 1) | Band 2 (Digit 2) | Band 3 (Multiplier) | Band 4 (Tolerance) | Band 5 (Voltage) |
|---|---|---|---|---|---|
| Black | 0 | 0 | x1 | ±20% | 4V |
| Brown | 1 | 1 | x10 | ±1% | 6.3V |
| Red | 2 | 2 | x100 | ±2% | 10V |
| Orange | 3 | 3 | x1,000 | - | 16V |
| Yellow | 4 | 4 | x10,000 | - | 25V |
| Green | 5 | 5 | x100,000 | ±5% | 32V |
| Blue | 6 | 6 | - | - | 40V |
| Violet | 7 | 7 | - | - | 63V |
| Grey | 8 | 8 | x0.01 | - | 100V |
| White | 9 | 9 | x0.1 | ±10% | 250V |
Rows People Get Wrong (And How to Fix Them)
When manually calculating values or verifying an online capacitor colour code calculator, hobbyists consistently trip over three specific areas:
- The Multiplier Trap: Unlike resistors where Gold and Silver represent x0.1 and x0.01 multipliers, capacitor multipliers rarely use metallic bands. If you see a Gold band on a tubular capacitor, it is almost certainly a tolerance band (±5% in some military specs) or a temperature coefficient indicator, not a multiplier.
- The 'Missing' Multiplier (3-Band Codes): If a capacitor only has three bands (e.g., Brown, Black, Yellow), the third band is the multiplier. Brown (1), Black (0), Yellow (x10,000) = 100,000 pF (100 nF). There is no tolerance band; assume a default of ±20%.
- Voltage Band Confusion: The 5th band indicates the DC working voltage, not the AC voltage. If you are using a 250V (White) rated capacitor in a 120V AC mains circuit, the peak voltage is ~170V, which is safe. However, for motor run applications, you must use a dedicated AC-rated capacitor, as DC voltage ratings do not account for AC dielectric heating.
Regional and Standard Variants: EIA vs. IEC vs. Old UK
Color coding for capacitors is largely a legacy technology, but you will encounter different standards depending on the era and origin of the equipment you are repairing.
| Standard | Region / Era | Application | Key Differences |
|---|---|---|---|
| EIA RS-279 | US / Global (1950s-Present) | Tubular ceramics, mica, paper | The standard table provided above. Base unit is pF. Read top-to-bottom on axial tubulars. |
| IEC 60062 | Global (Modern) | SMD and modern through-hole | IEC 60062 governs modern alphanumeric marking (e.g., '104' printed on ceramics). It does not define color bands for capacitors. Modern SMDs use no color codes. |
| Old UK BS (Pre-1960) | United Kingdom | Mica and paper capacitors | Used a 6-dot 'mica code'. The first dot indicated the temperature coefficient, not the first digit. Values were often in pF but required a specific lookup chart for the dot position. |
According to the Electronics Tutorials capacitor guide, if you are working on British equipment from the 1940s or 50s, do not apply the EIA table to 6-dot mica capacitors; you must source a specific BS (British Standard) mica dot chart.
Decision Path: Decoding Your Capacitor Manually
Use this decision-tree-table to terminate your identification process with a concrete replacement value or action.
| Condition Observed | Action / Calculation | Concrete Replacement Pick |
|---|---|---|
| 3 distinct color bands | Band 1 & 2 = Digits. Band 3 = Multiplier (zeros). Result is in pF. | Buy standard E12 series ceramic disc or film cap with matching pF value and ≥50V rating. |
| 4 or 5 distinct color bands | Band 1 & 2 = Digits. Band 3 = Multiplier. Band 4 = Tolerance. Band 5 = Voltage. | Buy C0G/NP0 (for <1nF) or X7R (for >1nF) MLCC or film cap matching pF, tolerance, and voltage. |
| Bands are present but colors are muddy/faded | Do not guess. Desolder one leg and measure with an LCR meter. | Measure at 1 kHz. Buy a modern WIMA MKS or Vishay MKP film capacitor with the measured value. |
| Capacitor is a silver mica 'blob' with dots | Identify as Old UK BS or EIA mica dot code based on equipment origin. | Buy Cornell Dubilier (CD) dipped silver mica capacitor matching the decoded pF value. |
Safe Interpretation When Markings Are Faded or Missing
Vintage tubular capacitors are notorious for 'migrating' wax and fading color bands, especially in high-heat environments like tube amplifiers or vintage radio IF (Intermediate Frequency) stages. When the visual calculator fails, you must rely on electrical measurement.
As noted in the All About Circuits reference on capacitor codes, visual degradation often accompanies dielectric degradation. If the colors are unreadable, assume the dielectric is also compromised.
- Isolate the Component: Desolder at least one leg of the capacitor from the circuit. Measuring in-circuit will yield false readings due to parallel impedance from surrounding resistors and coils.
- Select the Right Test Frequency: Set your LCR meter (like the DER EE DE-5000S or UNI-T UT612) to 1 kHz for ceramic and mica capacitors (values under 1 µF). If you are measuring a larger value paper/oil cap, drop to 120 Hz.
- Check Equivalent Series Resistance (ESR): If the measured capacitance is within 10% of your estimated target, but the ESR is above 5 ohms for a small ceramic, or the Dissipation Factor (D) is >0.05, the capacitor has internal micro-cracks and must be discarded.
- The Default Replacement Rule: If you cannot determine the exact original value, but you know the circuit function (e.g., a 1960s radio audio coupling cap), default to a 0.047 µF (47 nF) 400V metallized polyester film capacitor (like the WIMA MKS2 series). This covers 80% of legacy audio coupling and tone-stack applications safely.
