1. Resistor Color Code
2. Resistor Color Code 5 Band
3. Resistor Color Code
4. Resistor Color Code Chart

There are many different types of resistors available. In order to identify or calculate the resistance value of a resistor, it is important to have a marking system. Resistor Color Code is one way to represent the value of the resistance along with the tolerance.

4- Band Code 5- Band Code RESISTOR COLOR CODE GUIDE 2 0 x10,000 10% 20 x 10,000 = 200,000 1,000 = 1K Resistor = 200 K with a 10% Tolerance+-First Band Second Band Multiplier Band Tolerance Band Equation The Gold or Silver band is always placed to the right. The resistor value is read from the left to right.

• Our Resistor Color Code Calculator is a handy tool for reading carbon-composition resistors whether it's a 4-band, 5-band or 6-band type. To use this tool, simply click on a particular color and number and watch how the actual bands on the resistor illustration change.
• Determine the color code of a resistor and calculate resistors for LED circuits. By using this resistor calculator it is very simple to determine the color code of a resistor based on the resistor value. Of course, you can also provide a color code and the program will show you the resulting resistor value.
• The power rating of the resistor depends upon the physical size of the resistor. We consider as, a resistor consists of four different color bands (A, B, C, and D printed on the resistor body) as shown in the below figure.

Resistor color code is used to indicate the value of resistance. The standards for color coding registers are defined in international standards IEC 60062. This standard describes color coding for axially leaded resistors and numeric code for SMD resistors.

There are several bands to specify the value of resistance. They even specify tolerance, reliability and failure rate. The number of bands vary from three to six. In case of 3 band code, the first two indicate the value of resistance and the third band acts as multiplier.

Three Band Resistor Color Code

• The three band color code is very rarely used.
• The first band from the left indicates the first significant figure of the resistance.
• The second band indicates the second significant number.
• The third band indicates the multiplier.
• The tolerance for three band resistors is generally 20%.
• The color code table corresponding to three band resistors is shown below.

For example if the colors on the resistor are in the order of Yellow, Violet and Red from left, then the resistance can be calculated as

47× 102± 20 %. This is 4.7 KΩ± 20%.

This means the resistance value lies in the region of 3760Ω to 5640Ω.

Four Band ResistorColor Code

• Four band color code is the most common representation in resistors.
• The first two bands from the left are used to indicate the first and second significant digits of resistance.
• The third band is used to indicate the multiplier.
• The fourth band is used to indicate tolerance.
• There is a significant gap between third and fourth bands. This gap helps in resolving the reading direction. The color code table for four band resistors is as shown below.

For example, if the colors on a four band resistor are in the order Green, Black, Red and Yellow then the value of resistance is calculated as 50 * 104± 2 % = 500KΩ± 2%.

Five Band ResistorColor Code

High precision resistors have an extra band which is used to indicate the third significant value of the resistance. The rest of the bands indicate the same things as four band color code.

• The first three bands are used to indicate the first three significant values of resistance.
• Fourth and fifth bands are used to indicate multiplier and tolerance respectively.
• There is an exception when the fourth band is either Gold or Silver. In this case, the first two bands indicate the two significant digits of resistance.
• Third band is used to indicate multiplier, fourth band is used for tolerance and fifth band is used to indicate the temperature coefficient with units of ppm/K. The color code table for five band resistors is shown below.

For example, if colors on a five band resistor are in the order Red, Blue, Black, Orange and Gray then the value of resistance is calculated as 260×103± 0.05 = 260 KΩ ± 0.05%.

Six Band ResistorColor Code

• In case of high precision resistors, there is an extra band to indicate the temperature coefficient.
• The rest of the bands are same as five band resistors.
• The most common color used for sixth band is black which represents 100ppm/K.
• This indicates that for a change of 10⁰C in temperature, there can be a change of 0.1% in the value of resistance.
• Generally the sixth band represents temperature coefficient. But in some cases it may represent reliability and failure rate.

The color code table for six band resistors is shown below

For example if the colors on a six band resistor are in the order Orange, Green, White, Blue, Gold and Black then the resistance is calculated as 359 ×106± 5% 100 ppm/K = 359MΩ± 5% 100 ppm/K.

Tolerance Letter Coding for Resistors

The letter code for tolerance is shown below

• B = 0.1%
• C = 0.25 %
• D = 0.5 %
• F = 1 %
• G = 2 %
• J = 5 %
• K = 10 %
• M = 20 %

K and M should not be confused with kilo and mega Ohms.

SMD Resistor Code

There are three types of coding systems used to mark SMD Resistors. They are

• Three digit coding
• Four digit coding
• E96 coding

Three Digit Code

In three digit coding, the first two numbers indicate the significant value of the resistance and the third number indicates the multiplier like 10 in case the digit is 1, 100 in case the digit is 2 or 1000 in case the digit is 3 and so on.

A three digit coded SMD resistor is shown below

Some examples of three digit codes are

450 = 45 * 100 = 45 Ω

221 = 22 * 101 = 220 Ω

105 = 10 * 105 = 1 MΩ

If the resistance is less than 10Ω then the letter R is used to indicate the position of the decimal point. For example

3R3 = 3.3Ω

47R = 47 Ω

Four Digit Code

For more precision resistors, a four digit code is marked on them. The calculation is similar to three digit code. The first three numbers indicate the significant value of the resistance and the fourth number indicates the multiplier.

A four digit coded SMD resistor is shown below

Some examples under this system are

4700 = 470 * 100 = 470 Ω

1001 = 100 * 101 = 1 KΩ

7992 = 799 * 102 = 79.9 KΩ

For resistors less than 100 Ω, R is used to indicate the position of the decimal point.

For example,

Resistor Color Code

15R0 = 15.0 Ω

E series

Electronic Industries Association (EIA) specified a standard preferred value system for resistors and is named as E series. IEC 60063 is an international standard which defines the preferred number series in resistors (and also for capacitors, inductors and Zener Diodes). The coding is based on the tolerance values and different E series available are

• E3 50% tolerance
• E6 20% tolerance
• E12 10% tolerance
• E24 5% tolerance
• E48 2% tolerance
• E96 1% tolerance
• E192 0.5, 0.25, 0.1% and higher tolerances
• E3 coding is no longer in use and E6 coding is very rarely used.
• The E96 coding system is used for high precision resistors with a tolerance of 1%.

There is a separate coding system in EIA E96 marking system. This system uses three figures for marking. The first two are numerals which indicate the three significant digits of the value of resistance. The third figure is a letter used to indicate the multiplier.

The EIA E96 markings on an SMD resistor is

The EIA 96 code scheme for multipliers is shown below

The EIA 96 code scheme for significant values of resistance is shown below

Some examples of EIA 96 coding system are

92Z = 887 × 0.001 = 0.887 Ω

38C = 243 × 100 = 24.3 KΩ

Color Coding Table

The complete color coding table is shown below

Resistor color codes

How to read Resistor Color Codes

The 4-band code is used for marking low precision resistors with 5%, 10% and 20% tolerances. Identifying the value will become easy with a little practice, as there are only a few simple rules to remember:

• The first two bands represent the most significant digits of the resistance value. Colors are assigned to all the numbers between 0 and 9, and the color bands basically translate the numbers into a visible code. Black is 0, brown is 1, red is 2 and so on (see the color code table below). So, for example, if a resistor has brown and red as the first two bands, the most significant digits will be 1 and 2 (12).
• The third band indicates the multiplier telling you the power of ten to which the two significant digits must be multiplied (or how many zeros to add), using the same assigned value for each color as in the previous step. For example, if this band is red (2), you will multiply it by 10² = 100 (or add 2 zeros). So, for the resistor we used in the previous example, the value would be: 12 x 100 = 1200Ω (1.2kΩ).
  Note: If the multiplier band is gold or silver, the decimal point is moved to the left by one or two places (divided by 10 or 100).
• The tolerance band (the deviation from the specified value) is next, usually spaced away from the others, or it's a little bit wider. A color is assigned to each tolerance: gold is 5%, silver is 10%. 20% resistors have only 3 color bands - the tolerance band is missing.

The standard resistor color code table:

* 3rd digit - only for 5-band resistors

So, for a 560 ohm, 5% resistor the color stripes will be green, blue, brown and gold. Green and blue are the first significant digits (56); brown is the multiplier (10¹ = 10) and gold is the tolerance (5%). 56 x 10 = 560Ω.

If the 3rd band would be red instead of brown, the multiplier would be (10² = 100) instead of 10 and the resistor value would be 56 x 100 = 5600 ohms = 5.6 k ohms.

If the multiplier band is gold or silver, then the decimal point is moved to the left one or two places (divided by 10 or 100). For example, a resistor with green, blue, silver and gold rings has a value of 56 x 0.01 = 0.56Ω.

The 5-band code

The 5 band code is used for marking high quality, precision resistors with 2%, 1% or lower tolerances. The rules are similar to the previous system; the only difference is the number of digit bands. The first 3 bands will represent the value, the 4th band will be the multiplier and the 5th stripe will give us the tolerance.

Optional band

A few resistors have an additional band - often giving beginners a bit of trouble - indicating either the reliability or the temperature coefficient.

The reliability band specifies the failure rate per 1000 hours (assuming that a full wattage being applied to the resistor). This stripe is found primarily on 4-band resistors made for military applications and seldom used in commercial electronics.

Resistor Color Code 5 Band

The temperature coefficient is more commonly marked, especially on quality 5-band resistors, as it starts to become an important factor for precision components. For a resistor with temperature coefficient of 200 ppm, for example, a change in temperature of 50°C causes a value change of 1%. The most common values for this band are presented in the color chart above.

Examples:

Four band code:

Green, blue, red, with silver tolerance band: 56 x 100 = 5.6 kohms, with a tolerance of 10%

Brown, black, orange, gold tolerance band: 10 x 1000 = 10000 ohms (or 10K ohms), with a tolerance of 5%

Red, red, brown, silver tolerance band: 22 x 10 = 220 ohms (220 ohms), with a tolerance of 10%

More 4 band resistor color code examples: E12 and E24 series.

Five band code:

Blue, brown, white, brown, red tolerance band: 619 x 10 = 6190 ohms (6.19K ohms), with a tolerance of 2%

Red, red, brown, black, with a brown tolerance band: 221 x 1 = 221 ohms, with a tolerance of 1%

Brown, black, black, red, with a brown tolerance band: 100 x 100 = 10000 ohms (10.0K), with a tolerance of 1%

Standard EIA Decade Resistor Values

Resistors are available in standard values such as 1K, 2.2K, 4.7K, and so on. The two most common standards are the E12 and E24. You will notice that in the E12 series each succeeding value falls within +/- 10% of the previous value. The E24 range includes all of the E12 values, plus a further 12 to enable the selection of more precise resistances.

The E6 (20%) range is a subset of the E12 (10%) range and the E12 range is a subset of the E24 (5%) range. Similarly, the E48 (2%) range is a subset of the E96 (1%) range and the E96 range is a subset of the E192 (0.5% or less) range. Note, that the E24 range is technically also a subset of the E48 range, however, because of the different number of digits used for representation and rounding errors, the corresponding values in the two series do not match.

E6 series: (20% tolerance)
10, 15, 22, 33, 47, 68

Resistor Color Code

E12 series: (10% tolerance) - examples...
10, 12, 15, 18, 22, 27, 33, 39, 47, 56, 68, 82

E24 series: (5% tolerance) - examples...
10, 11, 12, 13, 15, 16, 18, 20, 22, 24, 27, 30, 33, 36, 39, 43, 47, 51, 56, 62, 68, 75, 82, 91

E48 series: (2% tolerance) - examples...
100, 105, 110, 115, 121, 127, 133, 140, 147, 154, 162, 169, 178, 187, 196, 205, 215, 226, 237, 249, 261, 274, 287, 301, 316, 332, 348, 365, 383, 402, 422, 442, 464, 487, 511, 536, 562, 590, 619, 649, 681, 715, 750, 787, 825, 866, 909, 953

E96 series: (1% tolerance)
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, 491, 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, 959, 976

Final thoughts

Resistor Color Code Chart

So, why all this trouble with color coding? The resistance value could be stamped or painted on the body of the through-hole resistor, no?

Yes, but the numbers would be quite small and difficult to read. If such a resistor is mounted with the marked side down, you cannot read its value unless you take it out of the circuit. Also, the markings would easily rub off or become smeared with time.

The resistor color code might seem a bit confusing and rather inconvenient at first, but most electronics hobbyists and technicians are surprised when they realize how quickly they've memorized the color chart without the use of mnemonics or other silly shortcuts.

The color code is quite intuitive, and after a brief familiarization period, instantly recognizing resistor values will come as second nature.