SnapShove is good, HRC is better if you’re doing desktop calculations. It can give you a world of preflop options beyond push-fold, and it’s pretty cheap.

I would recommend staying away from charts, even ‘dynamic’ ones – they’ll do you more harm than good in the long run. There are plenty of situations, particularly in low-stakes games, where relying on charts instead of simple, reliable reads on the player pool can leave a lot of money on the table.

Not to mention, charts are often wrong. Look at a 10bb middle position situation where everyone behind you has 11bb compared to one where everyone has 100bb, or where half have 30bb but half have 15bb, etc. – the results will all be different. I’ve seen charts be wrong by up to 5% in some situations.

The Riceman said
Ginger said

“Look at a 10bb middle position situation where everyone behind you has 11bb compared to one where everyone has 100bb, or where half have 30bb but half have 15bb, etc. – the results will all be different. I’ve seen charts be wrong by up to 5% in some situations.”

I can sense I am about to walk into a face-palmer here. I can sense the danger but like a blind wizened old fool lost in the woods on a misty moonlit night as the wolves howl in the distance, I just can’t see it.

What difference does it make what the stacks are behind if hero has 10bb under chipEV? Unless by “dynamic chart” you are telling me there are ICM Nash push-fold charts availabe, which would be news to me. If there are, then no, I can’t see how they would be a lot of use.  

Collin touched on it, but I’ll expand.

Essentially, stack depth of the players behind affects how wide they can call or fold, and thus it affects how wide we can shove at Nash, because Nash assumes we adapt to all factors. One stack acting after us needs to bear in mind how many chips they’re risking in the event that someone behind them wakes up with a hand.

Here’s a couple of examples. Let’s assume that in this scenario, we have 10bb and are shoving from the BTN. Stacks ahead of us don’t matter.

1. If SB and BB both have 100bb. Here, if we assume that SB would have to rejam 100bb in order to call our shove, SB has to call super tight, since they have to risk 100bb in the event that BB wakes up with a hand. This allows us to shove wider. If we allow SB to call 10bb and then fold to a BB rejam, we have to shove tighter, since SB can call wider. I ran this on HRC and it gave me 52% shoving range with rejams only, and 44% when SB is allowed to just call. Obviously even this is not the same as a real-game spot, since BB would likely not rejam for 100bb versus an SB call.

2. If SB and BB both have 11bb. Here, SB only has to risk 11bb in the event that BB wakes up with a hand, so it’s easier for SB to call us. It’s also easier for BB to overcall us, since they’ll be getting decent odds to get into a three-way all-in. As a result, we only shove 43% here.

3. If SB and BB both have 50bb. Here, SB is allowed to call 10bb and fold to a BB jam, or isolate us themselves. Our shoving range is 46%, since SB widening up a little creates more three-way all-ins, which actually improves the EV of certain suited hands in our range.

4. If SB has 25bb and BB has 50bb. Here’s the really interesting one. SB is not going to call 10bb and leave themselves with 15bb behind here, so they’re playing a simple push-fold game versus our shove, only they’re risking more chips versus the BB than we are. Theoretically this should tighten up their calling range because they’re risking more, but what it actually does is allow them to shut the BB out of their equity more frequently (since the BB can no longer call 10bb to see a flop three ways), and prevent the BB from shutting them out of their equity by rejamming over a call. As a result, our shoving range shifts around again, to 44%.

5. If SB has 15bb and BB has 5bb. Here, the BB is priced into calling off fairly wide against us and is overcalling super wide once SB calls us, so we tighten up a little, back to just under 43%. 

6. If SB has 5bb and BB has 15bb. The opposite spot – it’s the SB who’s priced into calling wider, but the BB still has to call our 10bb and have good equity against us, so they can’t call quite so wide. We can now shove 46% again.

You can see from all this that while the 52% range was unrealistic since people aren’t rejamming 100bb, our Nash range here shifts around from 43-46% depending on stack configurations behind us. This is with just two players left to act – if we’re in MP, obviously there’s even more volatility, and if we were doing exploitative calculations, that would change everything even further.