Electrical
HtomH
Convert henries (H) to millihenries (mH).
Factor1 H = 1000 mH
Converter
H
Accepts numbers or expressions, e.g. 150 + 14.7
Result
mH
Rendered to 6 significant figures.
Formula
Formula
mH = H × 1000
Multiply any value in henries by 1000 to obtain the value in millihenries.
Worked example
Convert 1 H to mH.
- 01Start with 1 H.
- 02Multiply by the conversion factor: 1 × 1000 = 1000 mH.
Result1 H = 1000 mH
Conversion table
| H | mH |
|---|---|
| 1 | 1000 |
| 2 | 2000 |
| 5 | 5000 |
| 10 | 10000 |
| 20 | 20000 |
| 50 | 50000 |
| 100 | 1.0000e+5 |
| 200 | 2.0000e+5 |
| 500 | 5.0000e+5 |
| 1000 | 1.0000e+6 |
Reference values rounded to 5 significant figures for display.
FAQ
What is the conversion factor from H to mH?
1 H equals 1000 mH. To convert, multiply the value in henries by 1000.
How do I convert 1 H to mH?
1 H = 1000 mH. For any value, multiply by 1000.
How do I convert mH back to H?
Divide by the same factor — or equivalently, multiply by 0.001. So 1 mH = 0.001 H.
When would I need to convert henry to millihenry?
Inductance conversions between H and mH are used in transformer and reactor design, EMI filter sizing, switched-mode power supply development and sensor coil specification. Henries cover power-inductor and choke ratings; millihenries through nanohenries cover signal-path filters and high-frequency electronics.
Is the conversion exact?
Yes. Both H and mH are defined by exact SI relationships, so the displayed factor is exact (any rounding shown is only for display).