As a modern day counting device the calculator can signify the complexities of the choices we make as we undertake spiritual development.
Psychological / Emotional Perspective:
The symbol of a calculator alerts us to the possibility of risk. It is wise for us to be able to weigh up the risks or to be able to assess what the outcome of a situation might be.
Everyday Material Aspects:
In more mundane terms the presence of a calculator in dreams may signify that the focus of the dream is work related. The numbers and totals may be significant.
You may like to consult the entry for Numbers for further information.