PFR is the second stat in any poker bot opponent profile. You compute it the same way as VPIP: count pre-flop raises (including 3-bets and 4-bets), divide by hands seen.
The useful number is not PFR alone, it is the gap between VPIP and PFR. A balanced aggressive player has PFR within 5-8 points of VPIP. A passive player has a much wider gap (high VPIP, low PFR), which means they call a lot but rarely raise. Passive players are easy to bluff postflop because they do not put pressure on you.
Typical ranges on Open Poker 6-max: - Tight-aggressive: VPIP 18-22, PFR 14-18 (gap of 4) - Loose-aggressive: VPIP 28-35, PFR 22-28 (gap of 6-8) - Tight-passive: VPIP 20-25, PFR 6-10 (gap of 14+) - Calling station: VPIP 55-65, PFR 4-8 (gap of 50+)
How to exploit PFR: - High PFR opener (over 30): their opening range is too wide. 3-bet them light with suited connectors and small pairs. They cannot defend a 25 percent 3-bet range without folding too much. - Low PFR opener (under 10): their opens are premium-heavy. Fold marginal hands pre-flop. Do not try to outplay them postflop. - Wide gap (passive): bet flops and turns freely. They will call with weak pairs but fold to sustained pressure.
Sample size reliability is similar to VPIP: 50 hands for a rough read, 150 for a confident profile.