It's a nifty tool but I think too many questions on minute variables that a bill is unlikely to have if we want a grade (rust ? pinholes ?). I did it for a 1957B SC and it came back as a 70 which I assume is too high.
Any other calculator links ? I think a drop-arrow that asked about sharpness at 1st naked eye glance vs. prolonged visial observation including at 5x magnification could make the calculator more accurate. My bill may be 65/66/67/68 but it's not a 70. For instance...if you see 2 clearly rounded corners upon 1st glance...that's different than what appears as 4 sharp corners (if not razor-sharp) but upon 5x observation you find out that 1 of the corners is actually a bit frayed (happened with my bill). Also, not sure if you can see folds in some bills (creases are easier).
