Excel function MAX
The MAX function returns the highest number in a series.
1st method
Select the MAX function. In the "Number1" field, enter a data range, then click OK.

The highest number will be displayed.

2nd method
Select the MAX function. Enter one cell reference in each box (up to 255 boxes will be added automatically), then click OK.

The highest number will be displayed.

The 2nd method is generally used when the numbers are dispersed on the sheet.