Inductance Converter
Our free electrical & magnetic converter handles inductance conversions. See tables, ratios, and examples for quick reference.
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Adjust values & calculateAll Conversions
| Unit | Value |
|---|---|
| Henry (H) | 1.000000e+0 |
| Millihenry (mH) | 1.000000e+3 |
| Microhenry (uH) | 1.000000e+6 |
| Nanohenry (nH) | 1.000000e+9 |
| Picohenry (pH) | 1.000000e+12 |
| Kilohenry (kH) | 1.000000e-3 |
| Megahenry (MH) | 1.000000e-6 |
| Abhenry | 1.000000e+9 |
| Stathenry | 1.112650e-12 |
| Weber per ampere (Wb/A) | 1.000000e+0 |
Formula
Inductance conversion uses the henry as the base SI unit. All other units relate to the henry through metric prefixes or CGS system conversion factors. The conversion multiplies the input by the source unit factor to get henries, then divides by the target unit factor to produce the result.
Last reviewed: December 2025
Worked Examples
Example 1: RF Inductor Conversion
Example 2: Power Supply Choke
Background & Theory
The Inductance Converter applies the following established principles and formulas. Unit conversion is the process of expressing a quantity in a different unit of measurement while preserving its physical meaning. At the foundation of modern measurement lies the International System of Units (SI), which defines seven base units: the meter for length, kilogram for mass, second for time, ampere for electric current, kelvin for thermodynamic temperature, mole for amount of substance, and candela for luminous intensity. All other units, called derived units, are defined as algebraic combinations of these seven. Dimensional analysis is the principal method for performing unit conversions. By treating units as algebraic quantities that can be multiplied, divided, and cancelled, a conversion factor chain allows a value expressed in one unit to be rewritten in another without altering its physical magnitude. For example, to convert 60 miles per hour to meters per second, one multiplies by a chain of conversion factors each equal to one: (1609.34 m / 1 mile) × (1 hour / 3600 s). Metric prefixes enable compact expression of quantities across extreme ranges of magnitude. Standard prefixes span from nano (10^-9) through micro (10^-6) and milli (10^-3) up through kilo (10^3), mega (10^6), and giga (10^9), and beyond in both directions. These prefixes are strictly multiplicative and apply consistently to any SI base or derived unit. Temperature conversions require affine transformations rather than simple scaling. To convert Celsius to Fahrenheit the formula is °F = (°C × 9/5) + 32, while the conversion to the absolute Kelvin scale is K = °C + 273.15. These formulas reflect the different zero points and degree-size conventions of each scale. Significant figures govern how precision is preserved through calculations. A result should not express more precision than the least precise input value permits. In digital storage, IEEE and IEC standards distinguish between decimal prefixes (kilobyte = 1000 bytes) and binary prefixes (kibibyte = 1024 bytes), a distinction that has practical consequences for how storage capacity is reported by manufacturers versus operating systems. Unit coherence — ensuring that all quantities in an equation share a consistent unit system — is essential for obtaining correct results.
History
The history behind the Inductance Converter traces back through the following developments. Human beings have been measuring and comparing quantities since before recorded history. The earliest known measurement units were body-based: the cubit (the distance from elbow to fingertip), the foot, the hand, and the digit. The furlong originated as the length of a furrow a team of oxen could plow without resting. These anthropomorphic standards were practical for local use but differed between regions and kingdoms, creating persistent difficulties in trade and construction. The ancient Egyptians standardized the royal cubit at approximately 52.4 centimeters and distributed calibrated granite rods to ensure consistency across building projects, including the pyramids. Roman engineers used the mile (mille passuum, one thousand double paces) and spread these standards throughout their empire via road networks. Despite these efforts, measurement diversity persisted across medieval Europe, hampering commerce. The French Revolution created political will for radical standardization. In 1795 France officially adopted the metric system, defining the meter as one ten-millionth of the distance from the equator to the North Pole along the Paris meridian. This gave the world its first fully decimal, rationally constructed measurement system. The Metre Convention of 1875 established the International Bureau of Weights and Measures (BIPM) in Sevres, France, creating a permanent international body to maintain physical artifact standards and coordinate global metrology. For over a century, the kilogram was defined by a platinum-iridium cylinder locked in a vault near Paris. In 1999, a stark demonstration of what unit inconsistency costs occurred when NASA's Mars Climate Orbiter was lost because one engineering team used pound-force seconds while another used newton seconds. The spacecraft entered the Martian atmosphere at the wrong angle and was destroyed, at a cost of 327 million dollars. In 2019 the SI underwent its most significant revision, redefining all seven base units in terms of fixed numerical values of fundamental physical constants such as the speed of light, Planck's constant, and the elementary charge. This eliminated any reliance on physical artifacts and made the measurement system permanently stable and universally reproducible.
Frequently Asked Questions
Formula
Converted Value = Input x (From Unit Factor / To Unit Factor)
Inductance conversion uses the henry as the base SI unit. All other units relate to the henry through metric prefixes or CGS system conversion factors. The conversion multiplies the input by the source unit factor to get henries, then divides by the target unit factor to produce the result.
Worked Examples
Example 1: RF Inductor Conversion
Problem: An RF filter design calls for a 470 nH inductor. Express this in microhenries and millihenries.
Solution: 470 nH to uH: 470 / 1000 = 0.47 uH\n470 nH to mH: 470 / 1,000,000 = 0.00047 mH\nThis is a typical value for VHF/UHF filter circuits.
Result: 470 nH = 0.47 uH = 0.00047 mH
Example 2: Power Supply Choke
Problem: A power supply uses a 2.2 mH filter choke. Convert to henries and microhenries.
Solution: 2.2 mH to H: 2.2 x 10^-3 = 0.0022 H\n2.2 mH to uH: 2.2 x 1000 = 2200 uH\nThis choke smooths rectified AC in a linear power supply.
Result: 2.2 mH = 0.0022 H = 2200 uH
Frequently Asked Questions
What is inductance and what is a henry?
Inductance is the property of an electrical conductor that opposes changes in current flowing through it by generating an electromotive force (EMF). The henry (H) is the SI unit of inductance, named after American scientist Joseph Henry. One henry is defined as the inductance that produces one volt of EMF when the current changes at a rate of one ampere per second. It is equivalent to one weber per ampere or one volt-second per ampere.
What are typical inductance values in electronics?
Inductance values vary enormously across applications. Printed circuit board traces have parasitic inductances of a few nanohenries (nH). Surface-mount inductors for RF circuits range from 1 nH to 1000 uH. Audio crossover inductors typically range from 0.1 mH to 10 mH. Power supply filter chokes can be 1 mH to several henries. Large power transformers and reactors in electrical grids can have inductances of tens or hundreds of henries.
How does inductance relate to magnetic flux?
Inductance directly relates to magnetic flux through the equation L = N * Phi / I, where L is inductance in henries, N is the number of turns, Phi is the magnetic flux in webers, and I is the current in amperes. This means one henry equals one weber per ampere (Wb/A). A higher inductance means more magnetic flux is generated per unit of current, which is why inductors with more turns or magnetic cores have higher inductance values.
How do I calculate inductance of a solenoid?
The inductance of a solenoid is calculated using L = (u0 * ur * N^2 * A) / l, where u0 is the permeability of free space (4 pi x 10^-7 H/m), ur is the relative permeability of the core material, N is the number of turns, A is the cross-sectional area in square meters, and l is the length of the solenoid in meters. Adding a ferromagnetic core with high ur dramatically increases inductance compared to an air-core coil.
How accurate are the results from Inductance Converter?
All calculations use established mathematical formulas and are performed with high-precision arithmetic. Results are accurate to the precision shown. For critical decisions in finance, medicine, or engineering, always verify results with a qualified professional.
What inputs do I need to use Inductance Converter accurately?
Each field is labelled with the required unit (metric or imperial). Gather your source values before starting — for example, a weight measurement in kilograms, a distance in metres, or a dollar amount — and enter them exactly as measured. The formula section on this page lists every variable and explains what each represents.
References
Reviewed by Manoj Kumar, Mathematics Educator · Editorial policy