How to Measure an Inductor: 4 Easy Methods to Test Inductance

Knowing how to measure an inductor is important for electronics design, troubleshooting, quality inspection, and component selection. However, testing an inductor is not simply a matter of checking its resistance.

An LCR meter can directly measure inductance, while a standard multimeter is mainly useful for checking continuity and DC resistance (DCR). The right test method depends on what you need to verify.

In this guide, we explain how to measure an inductor and how to quickly check whether an inductor is working properly.

 

What Should You Measure on an Inductor?

The main parameters to check are:

Inductance (L): Usually specified in μH, mH, or H.

DC Resistance (DCR): The resistance of the winding.

Tolerance: The acceptable variation from the nominal inductance.

Rated current: Important for power inductors.

Insulation resistance: Important for certain shielded or core-based inductors.

For high-frequency applications, parameters such as Q factor and self-resonant frequency (SRF) may also be important.

 

How to Measure an Inductor with an LCR Meter

An LCR meter is the preferred instrument when you need to measure the actual inductance value.

Step 1: Check the Datasheet

Before testing, check the manufacturer's specifications for:

Nominal inductance

Inductance tolerance

Test frequency

Test voltage

DCR

Rated current

The test frequency is especially important because the measured inductance can vary with frequency and operating conditions.

Step 2: Select the Inductance Mode

Set the LCR meter to the appropriate inductance measurement mode.

If the instrument allows you to select the test frequency, use the frequency specified by the component manufacturer whenever possible.

Step 3: Calibrate the Meter

Perform the recommended open/short or zero calibration according to the LCR meter's instructions.

This is particularly important when measuring low-value inductors, where test-lead effects can influence the result.

Step 4: Connect the Inductor

Connect the two terminals of the inductor to the LCR meter and record the measured inductance.

Compare the result with the nominal value and tolerance in the datasheet.

For example, a 100 μH ±10% inductor should normally measure within approximately 90–110 μH under the specified test conditions.

 

How to Test an Inductor with a Multimeter

A standard digital multimeter normally cannot directly measure inductance. However, it can be used to check continuity and DC resistance.

1. Check Continuity

Set the multimeter to resistance or continuity mode and connect the probes across the inductor terminals.

A normal winding should have a finite resistance.

2. Check the Resistance

The DCR depends on the winding wire, number of turns, and inductor construction.

A low resistance does not automatically mean the inductor is defective. Many power inductors are specifically designed with low DCR to reduce power loss.

Always compare the measured resistance with the manufacturer's specification.

3. Look for an Open Circuit

If the meter shows OL or infinite resistance, the winding or connection may be broken.

This is a common indication of a damaged inductor.

Important: A Multimeter Does Not Normally Measure Inductance

A normal resistance measurement only tells you about the electrical continuity of the winding.

It does not confirm:

Actual inductance

Inductance tolerance

Q factor

Saturation characteristics

High-frequency performance

For accurate inductance measurement, use an LCR meter or another suitable AC measurement method.

 

How to Check Whether an Inductor Is Good or Bad

A quick inspection can be divided into three steps.

1. Visual Inspection

Check for:

Cracked housing

Burn marks

Broken terminals

Damaged insulation

Loose magnetic core

Signs of overheating

2. Continuity and DCR Test

Use a multimeter to check whether the winding is open and compare the DCR with the datasheet.

3. Inductance Test

Use an LCR meter to measure the actual inductance.

If the measured value is outside the specified tolerance, the component may not meet its intended performance.

For production testing, always use consistent test conditions so that measurements are repeatable.

 

Why Does Measured Inductance Differ from the Datasheet?

A small difference between the measured value and nominal value is normal.

Common reasons include:

Inductance tolerance

Different test frequency

Different test current

Temperature

Measurement equipment accuracy

Test-lead effects

Core characteristics

DC bias

For power inductors, inductance can also change as current increases because of magnetic core behavior.

Therefore, always compare your measurement with the manufacturer's specification under similar test conditions.

Inductor Testing: LCR Meter vs. Multimeter

Test Method	Inductance	DCR	Best Use
LCR Meter	Yes	Yes	Accurate component testing
Multimeter	Usually No	Yes	Continuity and basic troubleshooting
AC Measurement	Yes	Indirectly	Laboratory testing
Visual Inspection	No	No	Physical damage

For most engineering and quality-control applications, an LCR meter is the simplest choice for measuring inductance accurately.

FAQ

1.Can I measure an inductor with a multimeter?

A standard multimeter can normally measure continuity and DC resistance, but not actual inductance. Some advanced multimeters include an inductance function, but the measurement accuracy and test conditions should be checked.

2.How do I know if an inductor is bad?

First inspect the component for physical damage, then check continuity and DCR with a multimeter. If you need to verify the inductance value, use an LCR meter and compare the result with the datasheet.

3.What should a good inductor read on a multimeter?

A good inductor normally shows a finite resistance. The actual resistance depends on its construction and specifications. A very low resistance can be normal for high-current power inductors.

4.What is the best instrument for measuring inductance?

An LCR meter is generally the most convenient instrument for directly measuring inductance and related parameters.

 

Choose the Right Inductor for Your Application

Accurate measurement is only one part of selecting the right inductor. The correct component also depends on inductance, tolerance, DCR, rated current, core material, size, operating frequency, and application requirements.

Fullstar Electronics provides a wide range of standard and customized inductors, including SMD power inductors, shielded power inductors, high-current inductors, through-hole power inductors, and other magnetic components.

For example, Fullstar's SMD power inductors are designed for high-current applications and specify inductance test conditions, rated-current characteristics, and other electrical parameters.

If you need a customized inductance value, package, current rating, or mechanical design, contact Fullstar's engineering team to discuss your requirements.

Looking for a reliable inductor manufacturer? Contact Fullstar Electronics for standard or custom inductor solutions.

For more information, please contact us at sales@xfullstar.com