How can I format bytes a cell in Excel as KB, MB, GB etc?

Question

I have a value in a cell that\'s in bytes. But nobody can read 728398112238. I\'d rather it say 678.37GB

To write a formula to format it relatively easy (here\'s one

Answer 1

After seeing the answers here just improved on this formula to have decimal places on bigger values and cater for negative values.

=IF(A1<999500000000,TEXT(A1,"#,##.#0,,,"" TB"""),
IF(A1<-9995000000,TEXT(A1,"#,##.#0,,,"" GB"""),
IF(A1<-9995000,TEXT(A1,"#,##0,,"" MB"""),
IF(A1<-9995,TEXT(A1,"#,##0,"" KB"""),
IF(A1<-1000,TEXT(A1,"#,##0"" B """),
IF(A1<0,TEXT(A1,"#,##0"" B """),
IF(A1<1000,TEXT(A1,"#,##0"" B """),
IF(A1<999500,TEXT(A1,"#,##0,"" KB"""),
IF(A1<999500000,TEXT(A1,"#,##0,,"" MB"""),
IF(A1<999500000000,TEXT(A1,"#,##.#0,,,"" GB"""),
TEXT(A1,"#,##.#0,,,,"" TB""")))))))))))