How to add a memory size to an address range?

I know this is a very simple question but i'd like to know if there was an easy way to calculate rapidly an address by adding memory size to an initial address. For example I saw on forums people advising to "add" 32 Mio to an address.

So if i start at 0x00000000 and want to add 32 Mio :

1. I convert 32 Mio in 268435456 bits

2. I divide by the size of the words stored in the addresses ( it depends on the architecture, It's 8 bits per address in the machine i'm working on) : 268435456/8 = 33554432

3. I convert 33554432 in hex : 0x2000000

4. So my address would be 0x02000000 . right ?

Okay, it's quite simple ! But does someone knows an online tool to do that ? I could write a little script but i love online tools :)