Decode 4-band, 5-band, and 6-band resistor color codes with a live visual preview, calculate total resistance in series and parallel, find power dissipation, and compute voltage divider outputs — all 4 modes in one IEC 60062 verified tool.
✓Verified: IEC 60062:2016 Resistor Color Code Standard
Select resistor band countSelect band count.
First significant digit
Second significant digit
Third significant digit
Multiplier band
Tolerance band
Temperature coefficient (6-band only)
Brown | Black | Red | Gold
Enter up to 8 resistors in series (Rtotal = R1 + R2 + ... + Rn):
Resistance in ohmsEnter valid resistance.
Resistance in ohmsEnter valid resistance.
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+ Add more resistors (up to 8)
For current/power calculationsEnter valid voltage.
Enter up to 8 resistors in parallel (1/Rtotal = 1/R1 + 1/R2 + ...):
Resistance in ohmsEnter valid resistance.
Resistance in ohmsEnter valid resistance.
OptionalEnter valid resistance.
OptionalEnter valid resistance.
OptionalEnter valid resistance.
OptionalEnter valid resistance.
OptionalEnter valid resistance.
OptionalEnter valid resistance.
+ Add more resistors (up to 8)
For current/power calculationsEnter valid voltage.
Select calculation typeSelect calculation.
Resistor value in ohmsEnter valid resistance.
Voltage drop across resistor (or leave blank)Enter valid voltage.
Current (or leave voltage blank)Enter valid current.
Supply voltageEnter valid Vin.
Resistor between Vin and VoutEnter valid R1.
Resistor between Vout and GNDEnter valid R2.
Resistance
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⚠️ Disclaimer: Results based on IEC 60062:2016 color code standard and standard resistor formulas. Always verify component values with a multimeter for critical circuits. Resistor values may vary within tolerance range.
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📚 Sources & Methodology
All resistor color codes and formulas are verified against:
IEC 60062:2016 — Marking codes for resistors and capacitors, including color code bands iec.ch
IEEE Std 315-1975 — Graphic Symbols for Electrical and Electronics Diagrams standards.ieee.org
Complete Resistor Guide — Color Codes, Series & Parallel Formulas
Resistor Color Code Chart (IEC 60062)
Color
Digit
Multiplier
Tolerance
Temp Coeff (ppm/K)
Black
0
x1 Ω
—
250
Brown
1
x10 Ω
±1%
100
Red
2
x100 Ω
±2%
50
Orange
3
x1K Ω
—
15
Yellow
4
x10K Ω
—
25
Green
5
x100K Ω
±0.5%
20
Blue
6
x1M Ω
±0.25%
10
Violet
7
—
±0.1%
5
Grey
8
—
±0.05%
1
White
9
—
—
—
Gold
—
x0.1 Ω
±5%
—
Silver
—
x0.01 Ω
±10%
—
Series and Parallel Resistance Formulas
Series resistors simply add: the total is the sum of all individual values. Current is the same through each; voltage divides proportionally. Parallel resistors combine as reciprocals: the total is always less than the smallest individual resistor. Voltage is the same across each; current divides inversely proportionally to resistance.
Resistor Formulas (Ohm's Law & Power)
Series: Rtotal = R1 + R2 + R3 + ... + RnParallel: 1/Rtotal = 1/R1 + 1/R2 + ... + 1/Rn2 parallel: Rtotal = (R1 x R2) / (R1 + R2) (product-over-sum)N equal: Rtotal = R / NPower: P = V^2/R = I^2 x R = V x IVoltage divider: Vout = Vin x R2 / (R1 + R2)Current: I = V / R (Ohm's Law)
Standard Resistor Value Series (EIA)
Resistors are manufactured in standardized value series to cover the full resistance range with minimal waste. The E12 series (12 values per decade, 10% tolerance) covers: 10, 12, 15, 18, 22, 27, 33, 39, 47, 56, 68, 82 (and their multiples: 100, 120, 150... 1K, 1.2K... 10K, 12K...). E24 (5%) doubles the number of values. E96 (1%) provides 96 values per decade for precision applications.
Resistor Power Rating Selection
Always derate resistors to at most 50% of their rated power for continuous operation. A 0.25W resistor should carry no more than 0.125W. Common use cases: LED current limiting resistor (100–330Ω at 5V draws ~15–50 mA, dissipates 0.075–0.25W — use 0.25W minimum). Pull-up/pull-down (10K at 3.3V draws 0.33 mA, dissipates 0.001W — any rating works). High-power applications: motor braking, heater control, load resistors may need 5W–50W wirewound resistors.
💡
Color code memory trick: BB ROY Great Britain Very Good Wife = Black(0) Brown(1) Red(2) Orange(3) Yellow(4) Green(5) Blue(6) Violet(7) Grey(8) White(9). For tolerance: Gold = Good = 5%, Silver = So-so = 10%, Brown = Better = 1%. The gold/silver band is always on the right (toward the tolerance end), and is usually spaced further from the body than the other bands.
❓ Frequently Asked Questions
4-band: Band 1 = first digit, Band 2 = second digit, Band 3 = multiplier, Band 4 = tolerance. Brown-Black-Red-Gold = 1-0-x100-5% = 1,000 ohms (1K) ±5%. The tolerance band (gold/silver) is usually on the right and spaced apart from the body. Use the Color Code Decoder tab above and select your band colors for instant results.
1/Rtotal = 1/R1 + 1/R2 + ... For two: Rtotal = (R1 x R2)/(R1+R2). Example: 100 and 200 ohms in parallel: Rtotal = (100x200)/(100+200) = 20000/300 = 66.67 ohms. The total is always less than the smallest resistor. For equal resistors: Rtotal = R/N. Use the Parallel tab above for up to 8 resistors.
Rtotal = R1 + R2 + R3 + ... Simply add all values. 100 + 200 + 300 = 600 ohms. Series resistance is always greater than any individual value. Use series to limit current or create precise resistance values from standard parts. The same current flows through all series resistors; voltage drops are proportional to resistance.
P = V^2/R = I^2 x R = V x I. A 470-ohm resistor with 5V across it: P = 25/470 = 0.053W. Use a 0.125W (1/8W) resistor minimum; 0.25W is safer with 2x derating margin. For LED current limiting at 5V with 330 ohms: P = 25/330 = 0.076W — a standard 0.25W resistor is fine.
Tolerance is the allowed variation from nominal. Gold = ±5%, Silver = ±10%, Brown = ±1%, Red = ±2%. A 1K 5% resistor may measure 950 to 1050 ohms. For general use (LED limiting, pull-up, decoupling) 5% is fine. For op-amp gain networks, ADC references, precision filters — use 1% or better. 1% resistors use the 5-band code (3 digits).
Vout = Vin x R2/(R1+R2). Two equal resistors at any voltage produce exactly half. R1=10K, R2=10K, Vin=12V: Vout = 12 x 10/20 = 6V. Warning: voltage dividers only work accurately when the load resistance is at least 10x larger than R2. A microcontroller input (1M impedance) loading a 10K divider: 1M >> 10K — fine. A 100 ohm load on a 10K divider: Vout = 12 x (100||10000)/(10000+(100||10000)) ≈ 0.12V — heavily loaded.
E12 = 12 values per decade (10% tolerance): 10, 12, 15, 18, 22, 27, 33, 39, 47, 56, 68, 82. Multiply by 1, 10, 100... for all values. E24 (5%) = 24 values. E48 (2%) = 48 values. E96 (1%) = 96 values per decade. Most general-purpose resistors are E24 (5%). 1% precision resistors use E96 values. The spacing ensures the maximum error between the desired and nearest available value stays within the tolerance.
5-band: Bands 1, 2, 3 = three digits, Band 4 = multiplier, Band 5 = tolerance. Red-Red-Black-Brown-Brown = 2-2-0-x10-1% = 2200 ohms (2.2K) ±1%. The gap before the tolerance band is wider. If you cannot tell which end to start from, check: the gold/silver tolerance band is always last. 5-band resistors are almost always 1% precision types.
Through-hole: 1/8W, 1/4W (most common), 1/2W, 1W, 2W, 5W, 10W, 25W. SMD: 0402=1/16W, 0603=1/10W, 0805=1/8W, 1206=1/4W, 2512=1W. Always derate to 50% for continuous loads: a 0.25W resistor handles max 0.125W continuously. Increase ambient temperature further reduces rated power. High-power wirewound resistors (5W-50W) are used for braking resistors, dummy loads, and heating elements.
10K ohm 5% (4-band): Brown-Black-Orange-Gold (1-0-x1000-5%). 10K ohm 1% (5-band): Brown-Black-Black-Red-Brown (1-0-0-x100-1%). 10K is the most common resistor value used for pull-up/pull-down on microcontroller pins, I2C bus lines, and divider networks. At 5V, a 10K resistor draws 0.5mA and dissipates 2.5mW — negligible.
Solve in stages: first reduce parallel groups to a single equivalent, then add series resistors. Example: R1=100 in series with (R2=200 parallel R3=200). Step 1: R2||R3 = (200x200)/(200+200) = 100 ohms. Step 2: R1 + 100 = 200 ohms total. Work from innermost groups outward. Always label which resistors are in parallel vs series before calculating — a circuit diagram prevents errors.
0=Black, 1=Brown, 2=Red, 3=Orange, 4=Yellow, 5=Green, 6=Blue, 7=Violet, 8=Grey, 9=White. Memory: BB ROY Great Britain Very Good Wife. Multipliers: Gold=x0.1, Silver=x0.01 (only used when resistance is less than 10 ohms). Tolerance: Gold=5%, Silver=10%, Brown=1%, Red=2%, Green=0.5%, Blue=0.25%, Violet=0.1%.