How Big Should Your Open Raise Be?

Open 2.2 to 2.5bb online, 3bb or more in a live game where nobody folds, and add a big blind for every limper already in the pot. Those three numbers cover almost every open raise you will ever make. What changes between them is never your hand — it is how often the players behind you actually fold.

Start with the default sizes

One size from every seat, adjusted only for the game you are sitting in. These are the numbers that hold up:

Game	Standard open
Online 6-max cash	2.2 to 2.5bb
Online full ring	2.2 to 2.5bb
Live cash, no ante	3 to 4bb
Live cash with an ante or straddle	4 to 5bb
Tournament, 40bb or deeper	2 to 2.5bb
Tournament, under 25bb	2bb or a min-raise

Then add one big blind for every limper in front of you, in any game. Three limpers over a 3bb base makes it 6bb, and that is not an aggressive raise. It is the going rate for a four-handed pot.

Why online opens shrank to 2.5bb

The open raise is the widest bluff in poker. From the button you are raising 40 to 45% of hands, most of which want nothing to do with resistance, and the prize is the 1.5bb sitting in the blinds. Price it the way you would price any bluff.

Break-even fold frequency = your raise ÷ (your raise + the dead money already in the middle)

Open size	You risk	Dead money	Must work
2bb	2bb	1.5bb	57%
2.5bb	2.5bb	1.5bb	63%
3bb	3bb	1.5bb	67%
4bb	4bb	1.5bb	73%

Your open is not a pure bluff — you have equity in the pots you get called in, so the real threshold sits below every number in that column. The shape is the point. Each extra half a big blind demands a noticeable chunk more folding, and nobody folds more often because you raised bigger.

The other half of the argument is what happens once you are called. A 3bb open against a big blind who defends properly builds a larger pot in which your range is only modestly ahead, and larger pots magnify every postflop mistake, including yours. A thin range edge is a poor reason to inflate one.

Small opens also let you play more hands. Risking 2.2bb to win 1.5bb makes marginal button opens like K5o and 96s worth attempting; risking 4bb for the same 1.5bb does not.

Live games reward a bigger raise

Now change the assumption. In a typical live 1/2 or 2/5 game, three players call 2.5bb without breaking eye contact with their phone. Your fold equity is close to zero, so the raise stops being a steal and becomes a value bet into a field that will pay it.

• Charge the callers. If they are coming regardless, take more money from them with the better range. A 2.5bb open into five callers is a discount, not a raise.
• Thin the field. Every extra caller shreds the equity of the hands you open with. Going from four-way to heads-up is worth far more than the extra big blind costs you.
• Match the stack depth. Live stacks run 100 to 300bb. A bigger starting pot is the only way to get all the money in by the river with the hands that want to.

Limpers are why the number climbs fastest live. Add a big blind for each of them and raise anyway — the same maths that explains why open-limping loses money is what makes their limps so profitable for you to attack.

Antes push the size up again

An ante — a big blind ante in a tournament, a button ante or a straddle in a cash game — drops extra dead money into the middle before anyone acts. Two things follow, and they pull against each other.

There is more to win. With a 1bb ante in play, your 2.5bb open chases 2.5bb rather than 1.5bb, so it only has to work about half the time instead of 63%. That is why every ante game is a wider-opening game.

There is more reason to call. The big blind is getting the better price too, and will defend far wider than in an anteless pot. Charging that defence properly means adding size, which is why 4 to 5bb is correct in live ante and straddle games.

The exception is short-stacked tournament play. Under 25bb the chips you risk matter more than the pot you win, and a min-raise becomes the default open. The rest of how antes change preflop play covers the range adjustments that arrive alongside the sizing.

The size stays, the range moves

Most players try to solve position with sizing: 3bb from UTG, 2.5bb from the button. Do it the other way round. Hold the size still and change how many hands you play with it.

Look at the UTG opening range and you find roughly 15 to 17% of hands — pairs, the big broadways, the top suited connectors — because five players still act behind you. From the button, 40 to 45% is right, because only two do. Same raise, wildly different range.

That single adjustment moves your win rate more than any sizing tweak available to you. It is also why opening ranges under the gun deserve a study session of their own: the seat where players are loosest is the seat where being wrong costs the most.

The mistakes that cost the most

The sizing errors that show up in real games are all variations on the same failure — reacting to your cards or your mood instead of the table.

• Sizing by hand strength. Raising 4bb with QQ and 2.2bb with 87s is the cheapest read anyone will get all night. One size, whole range.
• Importing online sizing into a live game. A 2.5bb open in a game where five players call is a bargain you are handing out for free.
• Ignoring limpers. Raising 3bb over three limps means four players see a flop for a rounding error, and you rarely have the best of it four ways.
• Sizing up when you are losing. Tilt sizing is transparent, and everyone at the table spots it before you do.
• Min-raising 100bb deep with no ante. The big blind needs around 22% equity to call, so nothing folds, and you play every flop against a range containing literally everything.

Pick your size before you sit down

1. Choose one number for the game. 2.5bb online, 3bb live, 4bb in a straddled or ante game. Use it with every hand you open.
2. Add a big blind per limper. Automatic, no thought required, no exceptions.
3. Check whether folds actually exist. After one orbit, ask how often an open goes through uncontested. If the answer is never, raise the size until calling costs them something.
4. Fix the range, not the size. Working through position-by-position opening charts seat by seat is the highest-value hour in preflop study.

Sizing is the easy half of the problem. Every big blind you add to an open is another big blind risked to win the same 1.5bb, so add it only when the players behind you have shown you it will get called. They almost always show you within an orbit.