Same here. I don't believe it to be a good indicator.

But if s/he ever goes out in a bikini... (more than likely s/he won't) And you see that her belly button is lower than her waistline she is more likely a female than a male. Men have belly buttons equal to their waists. I find this to be much more accurate than finger lengths. https://9gag.com/gag/aOvBAGE

Same on my left hand. 100% woman here as well. This is a myth. Probably a better tell is to look at how they stand. Men stand differently and walk differently due to the pelvis.