Reversible resistor color code calculator.
Bidirectional (color to value decoder & backwards calculator: value to color ). 

Standard EIA Decade Resistor Values

Possibilities of resistor color code calculator.

Resistor color code calculator (above) gives you the opportunity to learn resistor value and its tolerance regardless of how many color bands is contained in its color code. Decoding produced in accordance with IEC 60062 and JIS C 0802 , but if it possible, takes into account the features of some manufacturers (e.g., Vishay) .

Calculation from color to value: to get the result you should select a number of color bands, and assign a color to each of them. Directly under the resistor the result will be displayed in the form X*10^Y Ohm . In the field below (RESULT), the same result will be displayed in the form of Ohm, kOhm or MOhm. In the drop down menu below each strip is a list of colors and numbers, which correspond to them. Invalid color for the strip, located in this position, in the resistor color calculator designated as "---". In determining the value of resistor by colors calculator serves as the resistor color code decoder.

 Calculation from value to color: if you need to know what color code corresponds to a value of resistance, then: select range (Ohm, kOhm, Mohm) from drop-down menu, enter value in RESULT field (digit only, e.g. 123, 12.3, 1.23, 0.123),  choose tolerance. Color of bands on the resistor image will be recalculated accordingly. For example, if you are concerned about the question "Which is the colors for 1kOhm resistor?", you must enter the number "1" in the "Result" and select the item "kOhm" in drop-down menu calculator. Keep in mind, if you have not choose tolerance, often several options color code possible (eg 110 ohms, depending on the accuracy, could have 4 or 5 band), but will be offered only one of them! If you do not specify tolerance, defaults resistor color code will be calculated as follows: first, the code will be designed for a 5% resistor (4 bands). If 5% resistor with this value does not exist, will be calculated code for 1% resistor (5 bands). If 1% does not exist too ..... you will see the code 0.5% resistor (even if 0.5% resistor with this value does not exist).

In both cases in the information field below , you will get the message to any number of standard resistance values applies the resulting value. If the value does not belong to any of the standard series or the tolerance does not match the accuracies of standard series, which belongs to the denomination, then most likely you make a mistake in determining the color of any stripe.
Sometimes it is difficult to determine which of the bands first. In this case, you can help button "REVERSE". When it clicked, resistor color code is read in reverse order (from right to left). In most cases, one variant of color code will definitely wrong, what message will appear.

In addition, for the convenience of the right table displays the standard values of the series E12, E24, E48, E96, E192. Every time you choose a calculator new color code, table will scroll to the nearest to the entered value of the standard denominations.
The lower the information field of color calculator duplicated by words the color bands, or performs the functions of detector errors, i.e. notify you of errors and inconsistencies in the code. In case of errors displayed button "CORRECT". Clicking on this button color code calculator will offer one of the true option. When the page loads, resistor color code calculator switches to demo mode. In this case, the strips resistor color code is automatically in random order change color and calculated nominal, the resulting labeling is appropriate. This mode is disabled when you themselves try to introduce resistor color bands. Calculator resistor color code is also available in Spanish, Portuguese, German, Chinese and Russian. Links to these calculators are located in the upper left corner.

You can change the color of bands in resistor color code calculator by several ways:

• choose a color from the drop-down menu located under the strip
• click the "+" and "-" buttons located above the strip, in this case the increase or decrease by one digit, which is responsible for the selected band.
• click on the value in the table of EIA values, and the color of resistor bands is calculated by matching the value. In this cases the order of magnitude of resistance remain in the same range as was (kOhm, Ohm...).
• click on value in list of examples 5% (column on the right) and 1% tolerance resistor color code (on the left ). Color code calculator will recalculate the color and number of bands in accordance with the chosen value.
• enter value in "RESULT" field and select from drop-down menu range (Ohm, kOhm, MOhm) and tolerance.

Examples of marking and tables with resistor color code:

The Electronic Industries Association (EIA) specify standard values for resistors, sometimes referred to as the "preferred value" system. The preferred value system has its origins in the early years of the last century at a time when most resistors were carbon-graphite with relatively poor manufacturing tolerances. The rationale is simple - select values for components based on the tolerances with which they are able to be manufactured. Using 10% tolerance devices as an example, suppose that the first preferred value is 100 ohms. It makes little sense to produce a 105 ohm resistor since 105 ohms falls within the 10% tolerance range of the 100 ohm resistor. The next reasonable value is 120 ohms because the 100 ohm resistor with a 10% tolerance is expected to have a value somewhere between 90 and 110 ohms. The 120 ohm resistor has a value ranging between 110 and 130 ohms. Following this logic, the preferred values for 10% tolerance resistors between 100 and 1,000 ohms would be 100, 120, 150, 180, 220, 270, 330 and so on (rounded appropriately); this is the E12 series shown in the table above. The EIA "E" series specify the preferred values for various tolerances. The number following the "E" specifies the number of logarithmic steps per decade. The values in any decade can be derived by merely dividing or multiplying the table entries by powers of 10.

The series are as follows:
E6 20% tolerance (3-band resistor color code)
E12 10% tolerance (4-band resistor color code)
E24 5% tolerance (4-band resistor color code)
E48 2% tolerance (5-band resistor color code)
E96 1% tolerance (5-band precision resistor color code)
E192 0.5, 0.25, 0.1% and higher tolerances (5-band precision resistor color code) - resistors

While the "E" preferred value lists are the best way to insure one is stocking the optimum number of values for a given tolerance, a word of caution is in order with respect to what is actually available in the marketplace and certain real world practices. For instance, the E48 list is often used as a stock list for 1% resistors for inventory control (48 values per decade rather than 96), but this practice leaves "holes" or gaps in one's stock not covered by tolerance overlap, an undesirable practice in a prototype lab (less of an issue to the digital designer than to an analog circuit designer). The use of the E48 list for inventory control of 1% resistors works out well because every value on the E48 list just happens to also appear on the E96 list; the holes are thus symmetrical and easily filled by acquisition of one of the other 48 values per decade being omitted from stock. However, this is not always the case as can be seen by comparing the E24 and E96 lists. Nevertheless, many manufacturers make every single value on the E24 list in 1% tolerance even though the practice makes little mathematical sense (think about the obvious tolerance overlap between the 120 and 121 values for instance). Stocking only the E24 series in 1% will result in less symmetrical holes in stock than the practice of stocking only the E48 series. In any event, one should be aware of these practices to avoid confusion.
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Button "M+":
It remembers the color markings of resistors, which you have chosen. If you enter a color code from the color select menu or by using the "+" and "-" button, then to store the color code need to click the "M +" button. In other cases the value is stored automatically. This function of color code calculator handy if you need to learn a few color-coded resistors. Values with the wrong color code (discrepancy with standard resistor values or tolerances) are highlighted in red.
Button "MC":
Clear all color code from memory of calculator.