Inspired by another thread and the fact that I'm a total nerd, here are some common 'mistakes' people make at blackjack. We all know the mistakes, but what do they cost? For the purpose of this discussion, I'm working off of a $10 bet. It's all linear, so if you bet $100, simply multiply the mistake value times 10. This is based on a neutral count deck. I'm not figuring out numbers for specific counts. EV is expected value. That is, if you play this hand a million times, your average return. Player 16 vs dealer 10 showing Hit EV is $4.60 Stand EV is $4.60 Surrender EV is $5.00 (obviously) In this example you surrender unless you can't. If you can't surrender, to figure out the difference you have to take it to a third decimal place...meaning your 'mistake' is costing you less than a penny. 6 tenths of a cent, to be exact. So you should hit, but if you don't, I wouldn't worry about it. Player 16 vs dealer 7 showing. Hit EV: $5.85 Stand EV: $5.25 This one is for my brother, who likes to stand on 16 vs a dealer 7. The mistake costs you 60 cents...it's actually more wrong than standing on 16 v a dealer 10, which is kind of counterintuitive Splitting 10s vs a dealer 6 Stand EV: $17.04 Split EV: $14.68 Never split 10s. Ever. Not splitting 8s vs a dealer 10 Hit EV: $4.60 Stand EV: $4.60 Surrender EV: $5.00 Split EV: $5.19 I hate splitting 8s vs a dealer 10. A lot of people do. And surrendering isn't a huge mistake at 19 cents. But the correct play is to split them. For the record, it's even a bigger mistake not to split them against a dealer Ace. I'll post a few more in another post. If you've got one that you want to know, feel free to ask it. I've got a spreadheet to calculate it. As I may have mentioned before, I'm a total nerd.