Corrente RMS
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
Formula
I_rms = I_pico/√2
About this calculator
The RMS (Root Mean Square) current calculator converts the peak value of a sinusoidal alternating current into its effective value, also known as RMS current. The formula used is I_rms = I_peak / √2, where I_peak is the maximum current amplitude. This effective value represents the equivalent DC current that would produce the same power dissipation in a resistor.
This tool is essential in electrical and electronic projects, such as sizing cables, fuses, and components. For example, when designing an LED lighting circuit, you use RMS current to ensure components handle the dissipated power. It is also useful in power quality analysis, where harmonics and distortions are measured.
Caution: the relationship I_rms = I_peak / √2 only applies to perfect sinusoidal waves. For non-sinusoidal waveforms (like square or triangular waves), the crest factor differs. Also, remember that RMS value is always less than peak value, and do not confuse it with average current, which is zero for a symmetrical sine wave.
Use the calculator whenever you need to convert between peak and RMS values in AC circuits. It is particularly useful in electronics labs, equipment maintenance, and circuit simulations. Verify that your current source is sinusoidal before applying this formula.
Frequently asked questions
What does RMS current mean?
RMS (Root Mean Square) current is the effective value of an alternating current, equivalent to a DC current that would produce the same power in a resistor.
Does the formula I_rms = I_peak/√2 apply to any waveform?
No, only for perfect sinusoidal waves. For other waveforms, the conversion factor is different.
Can I use this calculator for non-sinusoidal AC current?
No, because the formula assumes a sine wave. For non-sinusoidal waves, you need to calculate RMS by integrating the waveform.
What is the difference between RMS current and average current?
The average current of a symmetrical sine wave is zero, while RMS current is positive and represents power dissipation.
Why is RMS value important in electrical circuits?
Because it determines the current-carrying capacity of cables and the power dissipated in resistors, essential for safe design.