Introduction to GTO Concepts

What Does GTO Mean?

GTO stands for Game Theory Optimal — a strategy that cannot be exploited by any opponent, no matter how they play. A GTO strategy is based on Nash equilibrium: if both players play GTO, neither can improve their results by changing strategy.

In practice, true GTO is computed by solvers — software that runs billions of simulations to find equilibrium strategies. No human plays perfect GTO, but understanding the concepts helps you build a solid, unexploitable baseline.

Why Mix Frequencies?

If you always raise your best hands and always fold your worst, opponents can predict your strategy and exploit it. GTO avoids this by mixing — sometimes raising and sometimes calling with the same hand, at specific frequencies.

For example, a hand like ATs from the cutoff might be a raise 80% of the time and a flat call 20% of the time in a GTO solution. This prevents opponents from knowing exactly what you have when you raise or call.

You can see these mixed frequencies on the GTO preflop charts. Each cell shows the raise frequency as a gradient — fully colored means always raise, half-colored means raise 50% of the time.

Indifference: The Core Idea

The heart of GTO is the concept of indifference. At equilibrium, certain hands are "indifferent" — they have exactly 0 EV whether they bet, call, or fold. This is by design: if a hand had positive EV from calling, you'd always call it, and your opponent could then adjust. Indifference prevents adjustment.

When you hear "GTO makes your opponent indifferent," it means your bluffing frequency is calibrated so that calling and folding produce the same result for your opponent. You bluff just enough that they can't profit by always calling or always folding.

Understanding the GTO Preflop Charts

The preflop chart page has a GTO mode (toggle at the top). Here's how to read it:

• Gradient bars: Each cell shows a colored bar. The filled portion is the raise frequency; the dim portion is fold (or flat call).
• 100% filled: Always raise this hand from this position.
• 50% filled: Raise half the time, fold (or call) the other half.
• No fill: Never open-raise this hand from this position.
• Position matters: The same hand has different frequencies by position. ATs might be 100% from the button but 30% from UTG.

The chart data represents open-raise (RFI) frequencies — what to do when no one has entered the pot before you. It does not cover 3-bet or cold-call scenarios.

GTO vs. Exploitative Play

GTO is a defensive baseline — it prevents exploitation. But against opponents with clear weaknesses, you can deviate from GTO to exploit them. This is called exploitative play.

• If a player folds too much: bluff more than GTO suggests.
• If a player calls too much: stop bluffing, bet only for value.
• If a player never 3-bets: open wider, steal more blinds.

The best players combine both — use GTO as a default, then deviate when they identify specific tendencies.

Minimum Defense Frequency

MDF (Minimum Defense Frequency) tells you how often you must continue (call or raise) against a bet to prevent your opponent from profiting with any bluff. The formula:

MDF = Pot Size / (Pot Size + Bet Size)

MDF connects directly to pot odds. If your opponent bets 50% pot, you need to defend at least 67% of your range. Folding more lets them profit by bluffing with any two cards.

Next Steps

• Explore the GTO preflop charts and compare raise frequencies by position.
• Understand equity — the foundation GTO builds on.
• Learn pot odds to see how MDF connects to calling decisions.
• Poker math cheat sheet for quick reference on MDF and break-even percentages.