# What is RMS volume? RMS, or root mean square, is a practical way to determine the average level of the signal, and it's close to how our ears perceive loudness.[^1] RMS is the square root of the mean square.[^2] The mean square is the mean of the squares of a set of numbers.[^3] RMS squares the values, averages those values over a period of time, then finds the square root of that.[^4] Why RMS? Simply averaging the values would not be helpful, since most signals vary between positive and negative, making the average usually around zero.[^5] RMS is also known as the [quadratic mean](https://brilliant.org/wiki/quadratic-mean/) in arithmetic.[^5] [^1]: [Gain Staging Like a Pro](https://www.sweetwater.com/insync/gain-staging/) [^2]: [What is "RMS (Root Mean Square)"?](https://www.sweetwater.com/insync/rms-root-mean-square/) [^3]: [Mean square - Wikipedia](https://en.wikipedia.org/wiki/Mean_square) [^4]: [[Audio Production and Critical Listening]] pg. 79 [^5]: [Root mean square - Wikipedia](https://en.wikipedia.org/wiki/Root_mean_square)