This calculator converts Peak Power to root-mean-square Power.
It also converts PRMS to Ppeak
Enter either value and it will compute the other.
PRMS = 0.7071 * Ppeak
Ppeak = (√ 2)* PRMS
RMS power, or root mean square power, is the continuous power output from an amplifier . Peak power on the other hand, is the maximum output power from the amplifier. An amplifier cannot operate at its peak for a sustained period of time.
🔎 Audio equipment manufacturers will often quote peak power. That can give the impression that an amplifier is capable of delivering more than it actually is. Look for the RMS power or use this calculator. In the world of radio frequency (RF) systems, an amplifier power specification is always an RMS value as is the corresponding voltage.
For 250 Watt RMS the equivalent peak power is 354 Watt.
 What’s the Difference Between RMS and Peak Watts? Electronic Design