Maybe I didn't look hard enough, but I couldn't find a generic, simple base translator that worked with floating point values (i.e. non-round numbers), so I made this. Weirdly, Javascript's native base conversion supports floating points in one direction but not the other. The ECMAScript spec is a bit ambiguous on this but I assume it's the same in all modern browsers.

Converting fractions may seem confusing at first but it's actually the same logic as whole numbers. When you have a number in base 10, say, 325.79, each digit tells you the multiple of a power of ten:

So you can see that the exponents of the base just carry on into negative numbers. I wonder why no one seems to bother.

Converting fractions may seem confusing at first but it's actually the same logic as whole numbers. When you have a number in base 10, say, 325.79, each digit tells you the multiple of a power of ten:

10^{2} | 10^{1} | 10^{0} | 10^{-1} | 10^{-2} | |

3 | 2 | 5 | 7 | 9 | |

300 | + 20 | + 5 | + 0.7 | + 0.09 | = 325.79 |