Changes the width of the columns in the range or the height of the rows in the range to achieve the best fit.
expression.AutoFit
expression Required. An expression that returns a Range object. Must be a row or a range of rows, or a column or a range of columns. Otherwise, this method generates an error.
Remarks
One unit of column width is equal to the width of one character in the Normal style.
Example
This example changes the width of columns A through I on Sheet1 to achieve the best fit.
Worksheets("Sheet1").Columns("A:I").AutoFit
This example changes the width of columns A through E on Sheet1 to achieve the best fit, based only on the contents of cells A1:E1.
Worksheets("Sheet1").Range("A1:E1").Columns.AutoFit