Thank you Sergey. Very nice concise code, it works very well, and it is very appreciated.

>>I am constructing a document number. It has several codes such as '05' of r fiscal year, and 'AB' for type, etc. It also has a two character counter imbedded in it, and it is space constrained (i.e. I am not able to expand the counter to three digits.) There needs to be room for 200 + items in any given set of numbers. Hexadecimal would take care of this, but I am not able to convert back and forth from binary to char. Currently there is a manual method that uses a table of alpha counters (AA, AB, AC, ... ZZ).
>>
>>Does that help?
>>
>
>Here's the code that will convert between integer and base36 in both directions

>DECLARE @i int, @cnt int, @Base36 char(36), @cnt36str char(2), @cntint int
>SET @cnt = 255
>SET @Base36 = '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ'
>
>-- Convert integer to base36 encoded 2 byte string
>SET @cnt36str = SUBSTRING(@Base36, (@cnt / 36)+1,1) +
>		SUBSTRING(@Base36, (@cnt % 36)+1,1)
>SELECT @cnt36str
>
>---
>
>-- Convert base36 encoded 2 byte string to integer
>SET @cntint = ( CHARINDEX(SUBSTRING(@cnt36str,1,1),@Base36) - 1) * 36 +
>		CHARINDEX(SUBSTRING(@cnt36str,2,1),@Base36) - 1
>SELECT @cntint
>