I just need a little clarification on this. I've seen a few different answers on this when I was studying this rule.

You multiple your outs on the flop by 4 if there is an all in on the flop. You multiply by 2 if there is no all in on the flop and you go on to the turn.

When I watch any poker tournaments on YouTube like past PCA's or EPT events. I noticed that when they are on the flop they use the percentages that would be the same as going from flop to river with no all in. Essentially using the 4 rule and not the 2 rule. They only use the 2 rule when they are on the turn. So my question is what is the right way to use the 4 and 2 rule?

Example:

HJ Raises folds to me on the BB and have 9s 8s and I defend.
Flop: As Qh 6s
I check and HJ makes a pot sized bet and I know this flop hits my opponents raise range. I'm sure I'm beat right now and know a flush is my only saving grace. So I have 9 outs times 2 will give my hand odds at around 18% or close to 4:1. The pot odds is giving me 2:1 and based on that I should fold. But if I use the 4x rule my hand odds will be 36% or close to 2:1 which is around the same as the pot odds and I would call.

That's an example of the dilemma with the 4 and 2 rule and the reason why I need some help with it.

do you always get to see both the turn and river?

https://forumserver.twoplustwo.com/3...2-4-a-1168512/

You're right. If you know you're gonna face a second barrel on the turn, then you apply the 2x rule instead of the 4x rule.

However, direct pot odds aren't everything. You can also account for "implied odds", which estimate the extra winnings you'll gain when you hit your flush. In practice, almost no one folds a strong flush draw on the flop.

If you wanna use these rules, take into account your BD (backdoor) draws.

A non-spade 7 gives you an OESD. A non-spade T gives you a double-gutter. (Apart from a spade, a non-spade T is the best turn card in the deck for you by a large margin.) A non-spade J gives you a gutshot. A non-spade 5 gives you a gutshot.

I think the classic Small Stakes Holdem book has a good rule-of-thumb for evaluating how much these BD draws are worth.

I'm a little rusty on this but it's gotta be worth at least one more out in addition to your nine flush outs.

Of course, as previous posters suggested, (direct) pot odds are most relevant if it goes all in or if you're playing LHE.

If, instead, substantial effective stacks remain after the flop action, implied odds become more important (i.e., what you can extract from your opponent on later streets when hitting your hand).

Hitting BD draws is particularly sweet as it can set some opponents on tilt.

EDIT: Don't underestimate your hand, it's quite strong. The fact that As is on the board also works in your favor (as it makes it less likely your opponent has a FD or BDFD himself).

For broadcasts, they use equity calculators to work out how often each hand will win if the hand got checked down all the way to showdown. The rule of 4 is a decent approximation for equity on the flop, and rule of 2 is OK for the turn.
But most hands don't get checked down. You have to consider pot odds and implied odds. In most cases this means you can call bets on the flop with draws, but - unless you have a particularly strong draw with tons of outs - you're often priced out on the turn.

Although, I believe it's more commonly referred to as all-in equity in the literature and various poker software. But yeah, it's the equity you got if there can't be further betting rounds (which is also the case when a player is ai in a HU situation OTF or two players are ai in a 3way situation OTF).

If you’re both deep on the flop and your opponent is the aggro type, times your flop outs by 2, if he is the passive type, then times your outs by 3. If you’re in position betting into a passive type then times your outs by 2 (cos you’ll almost always have a free card available against this type of player).

These are just ideas of mine

since someone raised it...

implied odds when you are OOP in the modern online game...very, very tough to realise them. DUCY?

Welcome to the forums ... I'm glad to see that you are getting some decent, and varied, responses. The Rule of 2/4 is usually pooh-poohed away, but it's a very good tool for newer Players to use so they can become familiar with approximate equities and make 'ABC' types of decisions.

Once you 'master' most of these situations then you can expand your thinking into some of the other variables involved in poker. Most opponents will 'never' give you the correct immediate pot odds to call. So you are either folding too much or you need to expand your thinking into ranges and implied odds to justify your 'bad' call.

A most glaring example is the one you bring up in your post. If you want to make 'ABC' decisions, then your opponent may have you priced into a call. But you only have a 9 high flush draw! So how often are you going to hit BUT your opponent has a bigger flush?

On a side note ... In all the shows, streams and content I've watched of Pros in both live and tournament play they are least afraid of flush draws. But on the flip side it's one of the most feared events in amateur play ... seeing the flush complete. It seems Pros are way more willing to just keep plodding away based on a card's rank (not the suit) and then deal with a possible flush after a call or raise has been made. Whereas a flush board is a perfect steal spot in most low limit poker action. GL

I only consider folding real flush and straight draws on the flop if I'm facing a very large bet.

in heads up pots your pair outs are almost always a non zero value on the flop.

In 3 way pots your pair outs are worth considerably less.

In 4 way pots your pair outs are likely negligible.

this is my number one concern with straight draws and flush draws facing normal sized bets on the flop.

my second concern is the probability that my opponent will check the turn.

my last concern is my opponents likely turn betsize, and any betsize tells that player may exhibit.

the combination of all these factors leads to some very different turn situations, where now folding seemingly strong draws can be correct facing above a certain betsize, or continuing with seemingly weak draws can be correct facing below a certain betsize.