Electronics decoder
Resistor Color Code Calculator
Decode 3, 4, 5, and 6 band resistor colors or reverse an ohm value into color bands.
Inputs
Results
- Resistance value
- Waiting for input
Use the controls above to decode a resistor with 3, 4, 5, or 6 color bands, or enter an ohm value to find a matching band sequence. The calculator updates as you select colors and shows the digit, multiplier, tolerance, and temperature coefficient roles separately.
Resistor Color Code Chart
| Color | Digit | Multiplier | Tolerance | Temperature coefficient |
|---|---|---|---|---|
| Pink (PK) | – | 0.001 | – | – |
| Silver (SR) | – | 0.01 | +/- 10% | – |
| Gold (GD) | – | 0.1 | +/- 5% | – |
| Black (BK) | 0 | 1 | – | 250 ppm/K |
| Brown (BN) | 1 | 10 | +/- 1% | 100 ppm/K |
| Red (RD) | 2 | 100 | +/- 2% | 50 ppm/K |
| Orange (OG) | 3 | 1,000 | +/- 0.05% | 15 ppm/K |
| Yellow (YE) | 4 | 10,000 | +/- 0.02% | 25 ppm/K |
| Green (GN) | 5 | 100,000 | +/- 0.5% | 20 ppm/K |
| Blue (BU) | 6 | 1,000,000 | +/- 0.25% | 10 ppm/K |
| Violet (VT) | 7 | 10,000,000 | +/- 0.1% | 5 ppm/K |
| Grey (GY) | 8 | 100,000,000 | +/- 0.01% | 1 ppm/K |
| White (WH) | 9 | 1,000,000,000 | – | – |
Code Structure
| Number of bands | Band 1 | Band 2 | Band 3 | Band 4 | Band 5 | Band 6 |
|---|---|---|---|---|---|---|
| 3 bands | Digit 1 | Digit 2 | Multiplier | Not shown, commonly +/- 20% | N/A | N/A |
| 4 bands | Digit 1 | Digit 2 | Multiplier | Tolerance | N/A | N/A |
| 5 bands | Digit 1 | Digit 2 | Digit 3 | Multiplier | Tolerance | N/A |
| 6 bands | Digit 1 | Digit 2 | Digit 3 | Multiplier | Tolerance | Temperature coefficient |
Three-Band Resistors
A 3-band resistor has two significant digits followed by a multiplier. It has no separate tolerance band, so common color-code practice treats the omitted tolerance as +/- 20%. Read the two digit colors first, then multiply by the third color.
Four-Band Resistors
A 4-band resistor uses two significant digits, a multiplier, and a tolerance band. The tolerance band is usually separated by a larger gap and is often gold or silver. For example, brown-black-red-gold is 1 kohm +/- 5%.
Five-Band Resistors
A 5-band resistor adds a third significant digit before the multiplier and tolerance. This format is common for precision parts. Brown-black-black-red-brown represents 10 kohm +/- 1% when the bands are read in that order.
Six-Band Resistors
A 6-band resistor has three significant digits, a multiplier, a tolerance band, and a final temperature coefficient band. The last value is normally expressed in ppm/K and describes resistance change with temperature; it is not another multiplier.
Calculating Resistance From Band Colors
- Count the visible bands and select the matching 3, 4, 5, or 6-band mode.
- Read the significant digit bands from the grouped end toward the separated bands.
- Multiply the significant digits by the multiplier band.
- Read tolerance when present; a 3-band resistor commonly uses the omitted +/- 20% convention.
- For a 6-band resistor, read the final band as temperature coefficient in ppm/K.
Finding Color Bands From Ohms
Enter an ohm value such as 4.7k, 1M, 4R7, or 1000 in the tool. It converts the value into a directly encodable band candidate for the selected band count. A mathematical match is not a guarantee that the exact value is stocked in a manufacturer series, so compare the result with the required tolerance and parts list.
Choosing the Reading Direction
Start where the significant digit bands are grouped together. A wider gap often appears before the tolerance band, and gold or silver are normally near the end rather than the first digit. If both directions look plausible because the part is faded, calculate both candidates and verify the value with the circuit documentation or an isolated meter reading.
Related Resistor Guides
- How to Read Resistor Color CodesRead the band count, significant digits, multiplier, tolerance, and temperature coefficient in the correct order.
- Resistor Color Code ChartA practical resistor color chart for digits, multipliers, tolerances, and six-band temperature coefficients.
- 3-Band vs 4-Band Resistor Color CodeLearn what changes between three-band and four-band resistor markings, including the assumed tolerance.
- 4-Band Resistor Color CodeDecode the most common through-hole resistor format: two digits, one multiplier, and one tolerance band.
- 5-Band vs 6-Band Resistor Color CodeDistinguish three significant digits, tolerance, and the extra temperature coefficient band in precision resistors.
- Resistor Color Code Tolerance BandsUnderstand what gold, silver, brown, red, and precision tolerance bands mean for the usable resistance range.
- Resistor Temperature Coefficient (ppm/K)Decode the sixth resistor band and understand how ppm/K describes resistance change with temperature.
- Which Way to Read a Resistor Color CodeUse spacing, color availability, and circuit context to identify the correct end of a resistor.
- Convert Ohms to Resistor Color BandsWork backward from an ohm value to a practical three-, four-, five-, or six-band color sequence.
- How to Read Faded Resistor Color BandsA cautious workflow for damaged, dirty, overheated, or low-contrast resistor markings.
- How to Verify a Resistor Value With a MultimeterMeasure a resistor safely and interpret why an in-circuit reading may disagree with its color bands.
- SMD Resistor Codes: 3-Digit, 4-Digit, R, and EIA-96Understand common surface-mount resistor markings and why package, manufacturer, and datasheet context matters.
- How to Read a 3-Digit SMD Resistor CodeDecode the supported three-digit SMD marking pattern by separating significant digits from the final multiplier digit.
- How to Read a 4-Digit SMD Resistor CodeRead four-digit SMD markings such as 1002 and 4701 by using three significant digits and a final multiplier digit.
- SMD Resistor R Decimal NotationUnderstand how R marks the decimal position in supported SMD resistor markings such as 4R7, R22, R010, and 0R22.
- Zero-Ohm SMD Resistor MarkingsIdentify the supported zero-ohm helper markings 0, 00, 000, and 0000 and verify the actual part series before use.
- How to Read the Confirmed EIA-96 SMD Resistor ExamplesUse the current decoder workflow for 01C, 68X, and 96D without treating the result as a substitute for the correct table or product series datasheet.
- SMD Resistor Nominal Value, Tolerance, and SpecificationKeep the decoded nominal resistance separate from tolerance, specification, package, and manufacturer verification in the product series datasheet.
- How to Verify an Ambiguous SMD Resistor MarkingKeep difficult readings as candidates and use package, manufacturer, board reference, and datasheet context before deciding what the mark means.
- Which Resistor Code Decoder Should You Use?Choose the decoder by the physical marking: through-hole color bands, a printed SMD resistor code, or a broader SMD component marking.
- Download Resistor Color Codes CSVCSV reference data for offline use.
Common Resistors And Color Codes
| Resistance value | 4-band color code | 5-band color code | Typical use |
|---|---|---|---|
| 1 ohm | Brown / Black / Gold / Gold | Brown / Black / Black / Silver / Brown | Low-value resistor |
| 10 ohm | Brown / Black / Black / Gold | Brown / Black / Black / Gold / Brown | LED and signal circuits |
| 100 ohm | Brown / Black / Brown / Gold | Brown / Black / Black / Black / Brown | General current limiting |
| 220 ohm | Red / Red / Brown / Gold | Red / Red / Black / Black / Brown | LED current limiting |
| 330 ohm | Orange / Orange / Brown / Gold | Orange / Orange / Black / Black / Brown | Digital outputs |
| 470 ohm | Yellow / Violet / Brown / Gold | Yellow / Violet / Black / Black / Brown | Signal circuits |
| 1 kohm | Brown / Black / Red / Gold | Brown / Black / Black / Brown / Brown | Pull-up or bias resistor |
| 2.2 kohm | Red / Red / Red / Gold | Red / Red / Black / Brown / Brown | Sensor and divider circuits |
| 4.7 kohm | Yellow / Violet / Red / Gold | Yellow / Violet / Black / Brown / Brown | Pull-up or divider circuits |
| 10 kohm | Brown / Black / Orange / Gold | Brown / Black / Black / Red / Brown | Common pull-up value |
| 47 kohm | Yellow / Violet / Orange / Gold | Yellow / Violet / Black / Red / Brown | Bias and timing circuits |
| 100 kohm | Brown / Black / Yellow / Gold | Brown / Black / Black / Orange / Brown | High impedance circuits |
| 1 Mohm | Brown / Black / Green / Gold | Brown / Black / Black / Yellow / Brown | High-value divider or input bias |
Download the Color Code Data
Download the resistor color codes CSV for an offline spreadsheet or reference. The download page explains the fields and their limits.
Decode logic
- Count the visible bands and select the matching 3, 4, 5, or 6-band mode: 3/4-band use two significant digits, 5/6-band use three.
- Read the significant digit bands from the grouped end, multiply by the multiplier band (gold x0.1, silver x0.01 for sub-ohm values), then read tolerance when a tolerance band is present.
- A 3-band resistor has no tolerance band; common color-code practice treats the omitted tolerance as +/- 20%. A 6-band resistor reads its final band as temperature coefficient in ppm/K.
- For reverse lookup, enter an ohm value such as 4.7k or 4R7 to get a directly encodable band candidate, then verify the bands against the physical part before relying on the value.
FAQs
Why does a 3-band resistor show +/- 20% tolerance?
A 3-band resistor has no printed tolerance band. In common resistor color-code practice, the omitted tolerance band is treated as +/- 20%.
Can the first resistor band be black?
The first significant digit band should not be black because it would make the leading digit zero. If the first band appears black, check whether the resistor is being read from the wrong direction or the marking is damaged.
How do I know which end to read from?
Read from the end where the significant digit bands are grouped together. Gold or silver tolerance bands, and bands spaced farther away from the others, are usually near the end of the code.
What does ppm/K mean on a 6-band resistor?
ppm/K is the temperature coefficient. It describes how much the resistance can change per kelvin of temperature change, expressed in parts per million per kelvin.
Can I use this output for purchasing or safety decisions?
Use this decoder as a marking aid only. Confirm safety-critical, procurement, power-rating, and compliance decisions with a multimeter, BOM, manufacturer data sheet, and the applicable standard.
How do I convert an ohm value back into color bands?
Enter a value such as 4.7k, 1M, 4R7, or 1000 in the Ohm field. The tool returns a directly encodable band candidate for the selected band count; a mathematical match is not a guarantee of a stocked part.