Inductance Conversion Made Easy: Henry, Millihenry & Microhenry Explained

Inductance is one of the core concepts in electrical engineering. It measures a component or circuit’s ability to store energy in a magnetic field, a property essential for devices such as transformers, motors, and electronic filters. Understanding how to measure and convert inductance is critical for anyone working with electronics.

The Henry: The Standard Unit of Inductance

The Henry (H) is the base unit for inductance in the International System of Units (SI). Named after Joseph Henry, an American scientist, one Henry represents the amount of inductance that produces one volt of electromotive force when the current through the circuit changes by one ampere per second.

In practice, most electronic circuits use inductors with much smaller values than a single Henry, which is why subunits of the Henry are commonly used.

Millihenry and Microhenry: Practical Subunits

Two smaller units make working with inductors much easier:

• Millihenry (mH): Equal to 1/1,000 of a Henry (0.001 H), millihenries are often found in medium-sized inductors, such as those used in power supply circuits or low-frequency filters.

• Microhenry (µH): Equal to 1/1,000,000 of a Henry (0.000001 H), microhenries are common in high-frequency electronics, such as mobile device antennas or RF modules.

Knowing these subunits helps engineers select the right components for their circuits without trial and error.

Simple Formulas for Converting Inductance Units

Converting between Henry, millihenry, and microhenry is straightforward because it involves factors of 1,000:

A quick tip: multiply when converting to smaller units, divide when converting to larger units.

Using Online Calculators for Precision

While manual calculations are simple, using an online inductance conversion calculator can save time and prevent errors, especially when dealing with multiple components or complex circuits. Many electronics suppliers offer free calculators that instantly convert between H, mH, and µH. These tools are invaluable for circuit design, prototyping, and troubleshooting.

Understanding these units and conversions ensures that your designs are precise and functional, whether you are working on hobby electronics or professional engineering projects.