This tool helps convert from **μV** (microvolt) to **dBµV** (deciBel microvolt).

Note that **μV** is a positive number that represents the root-mean-square (RMS) voltage and it cannot be less than zero.

**Formula**

**dBµV = 20*Log _{10}(µV)**

The same formula applies when converting either quantity scaled by distance (e.g. per-meter)

**dBµV/m = 20*Log _{10}(µV/m)**

**Background**

The dB scale is a very convenient representation for large numbers and allows for easy multiplication of two linear quantities.

**uV/m** or microvolt-per-meter is used by the FCC to specify radiated limits for RF equipment at a 3-meter distance from the source.

The first three columns of the following table of Radiated Emissions Limit is from [1]. The calculator is used to find the dBuV/m equivalent value

Freq. (MHz) | uV/m | dBuV/m | Distance (m) |
---|---|---|---|

30-88 | 100 | 40 | 3 |

88-216 | 150 | 43.5 | 3 |

216-960 | 200 | 46 | 3 |

Above 960 | 500 | 54 | 3 |

**Related Calculators**

Use this calculator to find the max transmit power (in dBm) for an equivalent dBuV/m power. This is a way to quickly calculate whether your transmitter is within the FCC specified emissions limit.