Calculate relative frequency from counts, and wave frequency, period and wavelength from each other.
wave frequency
How to use this tool
Type the count for each category, separated by commas — for example survey answers or outcomes.
Each count divided by the total gives its share, shown as a percentage.
Enter a period in seconds to get frequency in hertz, and a wave speed to get wavelength.
Cumulative relative frequency builds to 1.00 (100%) at the last category.
Formula & worked example
Counts 10, 20, 30 total 60, so relative frequencies are 16.7%, 33.3% and 50.0%. A wave with period 0.02 s has frequency 1 ÷ 0.02 = 50 Hz; at 343 m/s (speed of sound in air) its wavelength is 6.86 m.
Limitations — read this before you rely on it
Relative frequency describes the sample you entered; it is not a probability unless the sample represents the population fairly. Wave results assume a simple periodic wave and a constant wave speed — real waves in dispersive media vary with frequency.
Frequently asked questions
A count expressed as a share of the total. If 20 of 60 survey answers chose an option, its relative frequency is 20 ÷ 60 = 33.3%.
Frequency = 1 ÷ period. A wave repeating every 0.02 seconds has a frequency of 50 cycles per second (50 Hz).
Wave frequency counts cycles per second (Hz). Relative frequency is a data share (a proportion). They share a name but measure different things.
Divide wave speed by frequency: λ = v ÷ f. Sound at 343 m/s and 50 Hz gives 6.86 m.
Yes, if every observation is counted exactly once across all categories.