A list of numbers tells you almost nothing until it is organised. A frequency table is the first and most useful thing you can do to raw data — and it is built one column at a time, each column made from the one before it. Step through the build below; every number in the table is computed live from the data actually shown.
The raw data
The same data, binned
Build a frequency tablepress Next to add a column
10 min
48
Values (n)48
Classes (k)—
Busiest class—
Each column is built from the one on its left. f counts. Rel. f divides f by n. Cum. f adds f downwards. Cum. rel. f divides that running total by n. Four columns — three pieces of arithmetic.
Binning throws information away. Drag the class-width slider without changing a single data value. The same numbers can look smooth at one width and lumpy at another, and once the table is built you can no longer recover the values inside a class — only that they were in it. The shape a histogram shows is partly a choice its author made.