How to Read a Preflop Chart: the 13×13 Grid

Open any solved range and you get the same picture: a 13-by-13 grid of every starting hand, color-coded by action. It looks dense the first time, but the layout follows a few fixed rules, and once you know them a chart takes two seconds to parse. This guide covers the layout, the colors, mixed frequencies, the combinatorics underneath the grid, and how to read any chart without second-guessing yourself.

The layout

The grid is 13 ranks wide and 13 ranks tall, running A, K, Q, J, T, 9, 8, 7, 6, 5, 4, 3, 2 across the top and down the side. That produces 169 cells, which is exactly the number of distinct starting hands in Hold'em.

Three regions:

• Pocket pairs run down the diagonal from AA in the top-left corner to 22 in the bottom-right. Same rank on both axes.
• Suited hands sit in the upper-right triangle, above the diagonal. AKs, QJs, T9s, and so on.
• Offsuit hands fill the lower-left triangle, below the diagonal. AKo, QJo, T9o.

A quick trick: for any two-card combo, if it is above the diagonal it is the suited version, and below the diagonal it is the offsuit version. AKs is up top, AKo is down low. Once that clicks you never have to hunt for a hand again, because you already know which region it lives in before you look.

The combinatorics under the grid

Here is something most beginners never get told: the 169 cells are not equal in size. Each cell stands for a different number of actual card combinations, and that changes how you should think about them.

• A pocket pair cell is 6 combinations. There are 13 pairs, so 78 pair combos in total.
• A suited cell is 4 combinations, one per suit. There are 78 suited cells, so 312 suited combos.
• An offsuit cell is 12 combinations. There are 78 offsuit cells, so 936 offsuit combos.

Add those up and you get 1,326 total starting combinations, the real number of hands you can be dealt. The lesson: offsuit hands dominate the raw count, which is one reason the solve is so selective with them. When a chart folds most of the offsuit triangle, it is folding the single largest block of combinations in the deck, and doing it for a reason.

Why the shape looks the way it does

The playable hands are not scattered randomly. They cluster in the top-left, where the big cards and big pairs live, and thin out toward the bottom-right as hands get weaker. You will also notice the upper-right suited triangle stays colored in further down than the lower-left offsuit triangle. That is not a quirk. Suited hands make flushes and hold their equity better postflop, so the solve plays many more of them. Seeing that asymmetry at a glance is a good check that you are reading a real solve and not a rounded-off approximation.

Because the range fills from the top-left outward, learning the edge of a range, the weakest hands still played, is often faster than memorizing every cell. Everything above that boundary is usually in.

The colors

Each cell is colored by its action, and the set of colors depends on the spot:

• An opening (RFI) chart typically shows raise and fold.
• A facing-a-raise chart adds call, so you see 3-bet, call, and fold.
• 4-bet and blind-versus-blind spots can show even more branches, including limps in some structures.

The legend tells you which color is which. Always read the legend first, because the same color can mean different actions in different chart types. A chart is only meaningful once you know three things about it: the position, the action it is responding to, and the stack depth. The same seat has a completely different grid for "open" versus "facing a 3-bet."

Mixed frequencies: the part that trips people up

Here is what separates a solved range from an old-school chart. Many cells are not a single solid color. They are split, half one color and half another, and that is not a mistake.

A split cell is a mixed strategy. The solver has decided this hand sits right on the boundary between two actions, so it takes each action part of the time. A cell that is 60% raise and 40% fold means: across all the times you hold that hand here, raise it 60% and fold it 40%. Doing so keeps your range balanced so an observant opponent cannot pin you down.

Why mix at all? Because a hand that is exactly break-even between two actions can be played either way without losing EV, and mixing denies your opponent information. If you always folded that hand, a thinking opponent would know your raising range is a touch stronger than it should be, and could adjust. The mix closes that door. The exact frequency is what a real solve gives you and what a rounded-off chart throws away.

You do not need to nail every mix to a decimal. Play the pure actions correctly, lean to the heavy side of close mixes, and you have captured the bulk of the value. But when you want to get precise, you need the real numbers, and you need a way to randomize at the table, which players usually do with the suits of their cards or the second hand of a clock.

Two worked examples

Example one: A5s from the cutoff. You open the cutoff chart and find A5s in the suited triangle. The cell is split, most of it "raise" with a slice of "fold." That tells you A5s is a standard but not automatic open here: raise it the large majority of the time, and it is fine to occasionally fold it, especially if the table behind you is playing back aggressively. Now find A5o a row down in the offsuit triangle. It is mostly fold, because the offsuit version realizes less equity and represents 12 combos rather than 4. Same ranks, different region, different answer.

Example two: KTo facing a 3-bet. Switch to a "facing a 3-bet in position" chart at 100bb. KTo, which was a happy open, is now mostly a fold, with maybe a small call slice. Nothing about the two cards changed. The action in front of you did, and a hand that opens fine gets dominated when the money goes in. Reading the same hand across two charts is the fastest way to feel how much context drives the answer.

What the colors do not show

A preflop grid tells you the action and the frequency. It does not tell you two things you should keep in mind. First, it does not show how close a decision is. A hand raised 55% of the time is almost a coin flip between raise and fold, so a small change in conditions can flip it, while a hand that is a pure raise is not going anywhere. When you are learning, spend your attention on the pure actions and the heavily weighted mixes; the near-50/50 cells matter least because getting them slightly wrong costs almost nothing.

Second, the grid does not show postflop playability directly, even though the solve baked it in. A suited connector and an offsuit ace can have similar raw strength and completely different treatment, because one plays well after the flop and one does not. If a cell surprises you, the reason is usually playability, not a typo. Reading a chart well means trusting that the solve already accounted for what happens on later streets, so you do not have to re-derive it at the table.

A checklist for reading any chart

1. Read the label. Position, action being faced, stack depth. Without all three the grid is ambiguous.
2. Read the legend. Match every color to an action before you interpret a single cell.
3. Find the region. Pair on the diagonal, suited upper-right, offsuit lower-left.
4. Check for a mix. A split cell is intentional; note the dominant action and roughly how heavy it is.
5. Trace the edge. Learn the weakest hand still played in each region and everything above it comes along.

Run that checklist a few dozen times and it stops being a checklist. You will glance at a grid, register the label, and read the relevant region without consciously stepping through it, the same way a strong player reads a board texture at a glance. The goal is not to memorize 169 answers; it is to internalize the structure so any new chart is instantly legible.

Read them in Simple Preflop, not as screenshots

A static image of a chart hides the frequencies and freezes one spot. Solved files do not. Load them into the free Simple Preflop solver and you can move through positions, actions, and stack depths and see the actual mixed frequencies in each cell. New to the terms on the grid? The glossary has the definitions.

Once the grid makes sense, the next question is what a "range" really is versus a simplified chart: that is preflop charts vs ranges.