Instructions

This calculator finds standard resistor values that are closest to your desired value. Enter your target value in the Resistance field. Select the desired scale (Ω, kΩ, or MΩ) using the menu on the right side of the input field. The results will appear in the table below it.

The output data is organized by the resistor E-Series. Each row shows the series, its closest matching value, and the error compared to your target value.

Output format

The values appear in a table with three rows, one for each of the following resistor series E24(5%), E96(1%), and E192(0.1%). The table columns provide the following information:

• Value: This is the closest value in the resistor series.
• Error: This is the error in ohms found by subtracting the entered value in the Resistance field from the closest value in the resistor series.
• % Error: Provides the above error in percent instead of ohms.

Standard value terminology

The results are provided in common E-Series values. These values are used by resistor manufacturers. They correspond to resistor tolerances as follows:

• E24: 5% tolerance resistors are available in this series. 1% and lower tolerance resistors are often available in the E24 series as well.
• E96: 1% tolerance resistors are available in this series. 0.1% and lower tolerance resistors are often available in the E96 series as well.
• E192 Some 0.1% and lower tolerance resistors are found in this series. Resistor availability is more limited in this series.

Example

Let’s suppose that you need a 15.5kΩ resistor in your circuit. You’ll want to find out if this value is available in a standard resistor series that you can purchase. To do so, enter 15.5 in the Resistance field. You can leave the scaling at its default kΩ setting. The results will appear as shown below:

We can see that the closest standard E96 (1%) value available is pretty close at 15.4kΩ. It is 100Ω below our target value, corresponding to an error of -0.645%.

We can do better by combining multiple resistors using the Series & Parallel Resistor Solver. In fact, two standard resistors in series can yield an exact result

Other Features & Notes

Value ranges

This calculator limits the range of results from 1mΩ to 100MΩ.

More about standard resistor values

The standard resistor values used by this calculator follow the E series of preferred numbers. The E series includes several sets of numbers in the range of 1 to under 10. Manufacturers typically provide resistors with values within an E series and its multiples or ten. For instance, 1Ω, 10Ω, 100Ω, and so on.

For example, the E24 series is popular for 5% tolerance resistors. It consists of 24 numbers starting with 1.0, 1.1, 1.2 … and ending with 7.5, 8.2, 9.1. You’ll note that each value is about 10% larger than the previous value, or double the tolerance.

Similarly, 1% tolerance resistors are usually available in the E96 series, which are also spaced apart at roughly twice the tolerance. Things get murkier with tighter tolerances such as 0.1%. A few are available in closer spaced values like the E192 series, but most are only available in E96 or smaller series.