ERP ↔ EIRP Converter
Use this tool to convert between Effective Radiated Power (ERP) and Effective Isotropic Radiated Power (EIRP), based on dBm or watt values. The calculation accounts for the 2.15 dB difference between dipole and isotropic references.
Formula:
- EIRP [dBm] = ERP [dBm] + 2.15
- ERP [dBm] = EIRP [dBm] − 2.15
- EIRP [W] = ERP [W] × 1.64
- ERP [W] = EIRP [W] ÷ 1.64
Where:
2.15 dB = conversion factor (ERP uses a half-wave dipole reference; EIRP uses isotropic radiator)
Application Note:
This conversion is required when comparing or adapting RF test results for market access in regions with different radiated power standards.
- FCC (USA): typically requires ERP
- EU (CE): uses EIRP as standard reference
This tool helps with:
Comparing radiated power values across regulatory frameworks (e.g., FCC vs. CE)
Preparing test reports or technical documentation for international market approval
Ensuring consistency in RF power limits when adapting designs for different regions