Resistor Calculator
Decode 4, 5 and 6 band resistor color codes, find the code for any value with E series checks, and total resistors in series or parallel.
Yellow 4, violet 7, red ×100, gold ±5%
Start at the end where the bands bunch together. The wide tolerance band goes on the right.
Tolerance range
Gold tolerance band: the actual resistance may differ from 4.7 kΩ by up to 5% either way.
Your calculation
The same steps the calculator runs, with your numbers.
- Digits: yellow 4, violet 7 → 47.
- Multiplier: red ×100 → 47 × 100 = 4,700 Ω (4.7 kΩ).
- Tolerance: gold band ±5% → 4,700 × 5 ÷ 100 = ±235 Ω.
- Range: 4,700 − 235 to 4,700 + 235 = 4,465 Ω to 4,935 Ω.
Resistor color code chart
IEC 60062 values for every color, with your bands highlighted.
| Color | Digit | Multiplier | Tolerance | TCR | Your code |
|---|---|---|---|---|---|
| Black | 0 | ×1 | — | ±250 ppm/K | — |
| Brown | 1 | ×10 | ±1% | ±100 ppm/K | — |
| Red | 2 | ×100 | ±2% | ±50 ppm/K | Band 3 |
| Orange | 3 | ×1k | ±0.05% | ±15 ppm/K | — |
| Yellow | 4 | ×10k | ±0.02% | ±25 ppm/K | Band 1 |
| Green | 5 | ×100k | ±0.5% | ±20 ppm/K | — |
| Blue | 6 | ×1M | ±0.25% | ±10 ppm/K | — |
| Violet | 7 | ×10M | ±0.1% | ±5 ppm/K | Band 2 |
| Grey | 8 | ×100M | ±0.01% | ±1 ppm/K | — |
| White | 9 | ×1G | — | — | — |
| Gold | — | ×0.1 | ±5% | — | Band 4 |
| Silver | — | ×0.01 | ±10% | — | — |
| Pink | — | ×0.001 | — | — | — |
| None | — | — | ±20% | — | — |
Band meanings follow IEC 60062. An overheated resistor can drift outside its marked tolerance, so measure it if a circuit misbehaves.
How to Read Resistor Color Codes
This resistor calculator decodes the colored bands on through hole resistors, finds the color code for any resistance, and totals resistors wired in series or parallel. The color code is defined by IEC 60062, which gives each color a digit, a multiplier, a tolerance and, on 6 band parts, a temperature coefficient of resistance (TCR).
Which side to start reading from
Turn the resistor so the bands bunch toward the left end. IEC 60062 places the first band nearest one end of the body and makes the tolerance band at least 1.5 times as wide as the others, so the wide band goes on the right. Gold and silver never stand for a digit, so if either sits at the left end, the part is upside down. When the spacing gives no clue, use the "Read from the other end" button: usually only one direction gives a valid code and a standard value.
Reading the bands step by step
Write the digit for each digit band (two on a 4 band resistor, three on 5 and 6 band parts) and multiply by the multiplier band: black ×1, brown ×10, red ×100 and so on up to white at ×1,000,000,000, with gold ×0.1, silver ×0.01 and pink ×0.001. The next band is the tolerance, and a sixth band gives the TCR.
A memory aid for the digit order is "Better Be Right Or Your Great Big Venture Goes West", and red to violet follows the rainbow.
4 Band, 5 Band and 6 Band Resistor Codes
The band count tells you how many significant digits the value has and whether tolerance and TCR are marked. The examples below are the ones drawn in the figures of IEC 60062, including its 3 band code for ±20% parts.
| Bands | Layout | Example colors | Value |
|---|---|---|---|
| 3 | 2 digits, multiplier; no band means ±20% | Blue, grey, red | 68 × 100 = 6.8 kΩ ±20% (5.44 to 8.16 kΩ) |
| 4 | 2 digits, multiplier, tolerance | Violet, green, yellow, gold | 75 × 10,000 = 750 kΩ ±5% (712.5 to 787.5 kΩ) |
| 5 | 3 digits, multiplier, tolerance | Red, yellow, white, orange, brown | 249 × 1,000 = 249 kΩ ±1% (246.51 to 251.49 kΩ) |
| 6 | 3 digits, multiplier, tolerance, TCR | Red, yellow, white, orange, brown, red | 249 kΩ ±1%, ±50 ppm/K |
Since the 2016 edition of IEC 60062 the sixth band has normal width, because a wide TCR band was confused with the tolerance band. A 4 band code holds only two digits, enough for E12 and E24 values, while ±1% parts use E96 values such as 47.5 Ω that need a 5 band code.
What the Gold and Silver Bands Mean
In the last position of a 4 band resistor, gold means ±5% and silver ±10% tolerance: brown, black, red, silver is 1 kΩ ±10%, so 900 Ω to 1.1 kΩ. In the multiplier position they scale the value down, gold by ×0.1 and silver by ×0.01, which is how values below 10 Ω are marked. Yellow, violet, gold, gold is 47 × 0.1 = 4.7 Ω ±5%, and red, red, silver, gold is 22 × 0.01 = 0.22 Ω ±5%.
Resistor tolerance meaning
Tolerance is the largest allowed difference between the marked value and the actual resistance. A 220 Ω resistor with a gold band may measure anywhere from 209 Ω to 231 Ω and still be in specification. The tolerance colors in IEC 60062 are brown ±1%, red ±2%, green ±0.5%, blue ±0.25%, violet ±0.1%, orange ±0.05%, yellow ±0.02%, grey ±0.01%, gold ±5% and silver ±10%, and no band means ±20%.
Temperature coefficient: the sixth band
The TCR band states how much the resistance may change per kelvin, in parts per million (ppm/K): black ±250, brown ±100, red ±50, orange ±15, yellow ±25, green ±20, blue ±10, violet ±5 and grey ±1. Orange is tighter than yellow, so the TCR order does not follow the digits.
Series and Parallel Resistor Formulas
Resistors in series share one current path, so their resistances add. Resistors in parallel share one voltage, so their conductances (1/R) add and the total is always lower than the smallest resistor.
Two resistors in parallel formula
For exactly two resistors the reciprocal rule simplifies to the product over the sum, R1 × R2 ÷ (R1 + R2). For 220 Ω and 330 Ω, 220 × 330 = 72,600 and 220 + 330 = 550, so the total is 72,600 ÷ 550 = 132 Ω. Identical resistors divide evenly: n resistors of value R in parallel give R ÷ n, so two 1 kΩ make 500 Ω and three 330 Ω make 110 Ω.
5 kΩ is not in any E series, but two 10 kΩ resistors in parallel give exactly 5 kΩ, and 4.7 kΩ plus 300 Ω in series does the same with two E24 parts. When every part has the same tolerance, the combination keeps it, so two ±1% resistors give a ±1% total.
How voltage and current divide
In series the voltage divides in proportion to each resistance: 12 V across 1 kΩ, 2.2 kΩ and 4.7 kΩ gives 1.52 V, 3.34 V and 7.14 V. In parallel the current divides the other way, so the 1 kΩ resistor carries 59.98% of the total and the 4.7 kΩ resistor 12.76%. The Ohm's Law Calculator turns a total resistance into current and power.
Standard Resistor Values: E12, E24 and E96
Resistors are made in preferred values defined by IEC 60063. Each E series spaces its values evenly on a logarithmic scale, so every step is about the same percentage: 1.2115 times for E12, 1.1007 for E24 and 1.0243 for E96, the 12th, 24th and 96th roots of 10. The values repeat in every decade, so 4.7 Ω, 47 Ω, 470 Ω, 4.7 kΩ and 47 kΩ are all the same E12 value.
The number after the E is the count of values per decade. IEC 60063 pairs each series with a tolerance: E3 wider than ±20%, E6 ±20%, E12 ±10%, E24 ±5%, E48 ±2%, E96 ±1% and E192 tighter than ±1%.
E12 and E24 values
E12: 10, 12, 15, 18, 22, 27, 33, 39, 47, 56, 68, 82.
E24 adds: 11, 13, 16, 20, 24, 30, 36, 43, 51, 62, 75, 91.
E96 values for 1% resistors
Multiply each value by a power of 10: 475 stands for 4.75 Ω, 47.5 Ω, 475 Ω, 4.75 kΩ and so on. The list order is also the EIA-96 chip code, so 100 is code 01 and 475 is code 66.
100, 102, 105, 107, 110, 113, 115, 118, 121, 124, 127, 130, 133, 137, 140, 143, 147, 150, 154, 158, 162, 165, 169, 174, 178, 182, 187, 191, 196, 200, 205, 210, 215, 221, 226, 232, 237, 243, 249, 255, 261, 267, 274, 280, 287, 294, 301, 309, 316, 324, 332, 340, 348, 357, 365, 374, 383, 392, 402, 412, 422, 432, 442, 453, 464, 475, 487, 499, 511, 523, 536, 549, 562, 576, 590, 604, 619, 634, 649, 665, 681, 698, 715, 732, 750, 768, 787, 806, 825, 845, 866, 887, 909, 931, 953, 976.
Only six E24 values also appear in E96: 10, 11, 13, 15, 20 and 75. For a nonstandard 5 kΩ, the nearest values are 4.99 kΩ in E96 (0.2% low), 5.1 kΩ in E24 (2% high) and 4.7 kΩ in E12 (6% low).
SMD Resistor Codes: 3 Digit, 4 Digit and EIA-96
Surface mount resistors carry printed codes instead of bands, shown in the SMD marking tile, and the letter R marks the decimal point. A 3 digit code (E24 parts) is two digits and a count of zeros: 472 = 47 × 100 = 4.7 kΩ, 100 = 10 Ω, 4R7 = 4.7 Ω. A 4 digit code (±1% parts) is three digits and a count of zeros: 4701 = 4.7 kΩ, 1002 = 10 kΩ, 47R5 = 47.5 Ω.
Small 1% chips use EIA-96: the two digit position in the E96 list plus a letter, Y ×0.01, X ×0.1, A ×1, B ×10, C ×100, D ×1,000, E ×10,000 or F ×100,000. So 01C = 100 × 100 = 10 kΩ and 66X = 475 × 0.1 = 47.5 Ω.
Common Resistor Reading Mistakes
- Reading from the wrong end. Violet, green, yellow, gold read backward starts with gold, which is never a digit.
- Mixing up red, orange and brown under warm light. Measure when two readings both look plausible.
- Taking the 5th band as the multiplier. On 5 band parts the 4th band is the multiplier.
- Reading gold in the 3rd position as tolerance. There it means ×0.1.
- Stopping at 1/R1 + 1/R2. Take the reciprocal of that sum.
- Typing 4.7 with Ω selected for a 4k7 part. In Value to color mode, pick kΩ or type the RKM code 4k7 directly.
How to Measure a Resistor with a Multimeter
- Remove power and lift one lead, since parts in parallel lower the reading.
- Select Ω and, on a manual meter, the lowest range above the expected value, such as 20 kΩ for 4.7 kΩ.
- Keep fingers off both leads, which would put your body in parallel.
- Compare with the tolerance range. A 4.7 kΩ ±5% resistor reading 4.62 kΩ is in specification (4.465 to 4.935 kΩ).
Let a resistor cool after soldering before measuring. A reading far outside the range, or an open circuit, means the part has failed or is mislabeled.
Frequently Asked Questions
How do you read a 4 band resistor color code?
Hold the resistor so the tolerance band, usually gold or silver, is on the right. The first two bands are digits, the third band is the multiplier and the fourth band is the tolerance. For yellow, violet, red and gold, write 4 and 7 to get 47, multiply by 100 for the red band to get 4,700 Ω, or 4.7 kΩ, and read gold as ±5%. The resistor may measure anywhere from 4,465 Ω to 4,935 Ω.
What does the gold band on a resistor mean?
A gold band in the tolerance position, the last band of a 4 band resistor, means ±5%: a 1 kΩ resistor with a gold tolerance band may measure from 950 Ω to 1,050 Ω. A gold band in the multiplier position means ×0.1, so yellow, violet, gold, gold is 47 × 0.1 = 4.7 Ω with ±5% tolerance. Silver works the same way, with ±10% as a tolerance and ×0.01 as a multiplier. Neither color is ever used as a digit.
How do you calculate two resistors in parallel?
Multiply the two resistances and divide by their sum: R = R1 × R2 ÷ (R1 + R2). For 4.7 kΩ and 10 kΩ, 4,700 × 10,000 = 47,000,000 and 4,700 + 10,000 = 14,700, so the total is 47,000,000 ÷ 14,700 = 3,197.28 Ω. Two equal resistors in parallel give half of one value, so two 1 kΩ resistors make 500 Ω. For three or more resistors, add the reciprocals, 1/R1 + 1/R2 + 1/R3, and take the reciprocal of the sum. The parallel total is always lower than the smallest resistor.
What are the standard E12 and E24 resistor values?
IEC 60063 defines the E series of preferred values. The E12 series has 12 values per decade: 10, 12, 15, 18, 22, 27, 33, 39, 47, 56, 68 and 82. The E24 series adds 12 more: 11, 13, 16, 20, 24, 30, 36, 43, 51, 62, 75 and 91. Each value repeats in every decade, so 47 also stands for 4.7 Ω, 470 Ω, 4.7 kΩ and 47 kΩ. IEC 60063 pairs E12 with ±10% tolerance, E24 with ±5% and the three digit E96 series with ±1%.
What is the difference between 4 band and 5 band resistors?
A 4 band resistor shows two significant digits, a multiplier and a tolerance, which covers E12 and E24 values such as 4.7 kΩ at ±5%. A 5 band resistor shows three digits, a multiplier and a tolerance, which is needed for precision values from the E96 series such as 47.5 Ω or 249 kΩ, usually at ±1% or tighter. The same 4.7 kΩ reads yellow, violet, red on 4 bands and yellow, violet, black, brown on 5 bands.
Sources & References
- International Electrotechnical Commission. IEC 60062:2016+AMD1:2019 CSV, Marking codes for resistors and capacitors, edition 6.1, 2019 (color code, band order and width, TCR). webstore.iec.ch
- IEC 60062:2016+AMD1:2019 document preview, Table 1 Code colour prescriptions and Figures 1 to 4, iTeh Standards. standards.iteh.ai
- International Electrotechnical Commission. IEC 60063:2015, Preferred number series for resistors and capacitors, edition 3.0, 2015. webstore.iec.ch
- Vishay. Standard Series Values in a Decade, E3 to E192, document 28372. vishay.com
- Vishay. SMD resistor marking, document 20020 (3 and 4 digit chip codes). vishay.com
- Yageo. Chip resistor marking, Table 2 EIA-96 marking rule and multiplier letters. yageogroup.com
- OpenStax. College Physics 2e, Section 21.1 Resistors in Series and Parallel. openstax.org
- Nave, R. HyperPhysics: Resistance and Resistor Combinations, Georgia State University. HyperPhysics (gsu.edu)
Results are for education and design reference. Check the datasheet of the actual component for its rated tolerance, TCR and power limits. Every number on this page was recomputed with the same formulas the calculator uses. Methodology reviewed: 2026.