I have made a script to convert a number in any base between 2 and 36 to a number in another base between 2 and 36.
The program incorporates three keyboard (one for the input base, one for the output base and one for the number to converter).
Please observe that the actual converter supports unlimited precision and dies not convert via the decimal base as most converters do.

https://gist.github.com/8571abde6b3e47d8e3b2