Defending includes calls and three-bets
A big-blind defence range is not just a calling range. Premium hands can re-raise, other hands can call, and some hands mix actions. AJs and ATs are useful cells to compare because small changes in hand strength can change the preferred response.
A discount does not make every call profitable
You have already posted 1bb, so facing this open means adding 1.5bb to call. You will still play out of position, and cash-game rake affects marginal hands. Do not treat the price alone as a reason to continue with any two cards.
Match the opener and the sizing
These responses face a button open to 2.5bb, with three-bets to 13bb. An early-position raiser usually represents a different range, and a larger open changes the price of calling. Use this chart for its stated situation.
How to read a poker range chart
The 13×13 grid contains all 169 starting-hand classes in No-Limit Texas Hold’em. Pairs run down the diagonal, from AA to 22. Suited hands sit above it (AKs), and offsuit hands below it (AKo). T means ten.
The legend gives the action and total range percentage. A split cell means the hand mixes actions: 75% raise and 25% fold means raising three quarters of the time. It does not describe the hand’s chance of winning. Raise sizes are the total bet in big blinds, not the extra amount added.
Overall percentages count card combinations: each pair has 6, each suited hand 4, and each offsuit hand 12, for 1,326 combinations in total. Simply counting coloured squares would give a different, misleading percentage.
Can I use this chart when the small blind calls too?
No. This chart assumes the small blind folds. A caller makes the pot multiway and introduces squeeze decisions, which need a different strategy.
Using these charts
Changing stack depth, rake, opening size, or the number of players changes the situation. Study the assumptions alongside the hands.
Put the range into practice
Make decisions, get feedback, and track your accuracy in the preflop drill.
Practise this range