Calculate your tournament M-Ratio (Harrington's M) to determine optimal play based on stack depth and blind levels.
Your current chip stack
Number of players
Current small blind
Current big blind
Ante amount per player (0 if none)
M-Ratio
66.7
Zone
Green Zone
66.7 orbits left
Effective M
60.0
Adjusted for 9 players
Big Blinds
100.0
BB remaining
Cost Per Orbit
300
chips (blinds + antes)
Full range of plays available. Can play speculative hands and set mine profitably.
Quick-start with common scenarios
The M-Ratio (or M-Zone) tells you how many orbits you can survive before being blinded out. Calculate it as: Stack ÷ (Small Blind + Big Blind + Total Antes). An M of 20+ (Green Zone) allows full play, 10-20 (Yellow) requires tightening up, 5-10 (Orange) means push/fold approaching, and below 5 (Red Zone) is pure push/fold mode.
Full flexibility. Can play speculative hands, set mine, and use position. No pressure to act.
Tighten up. Focus on premium hands and position. Avoid marginal situations and speculative calls.
Push/fold approaching. Stop flat-calling opens. Look for spots to shove. First-in vigorish matters.
Pure push/fold mode. Never limp, never minraise. Shove or fold every hand. Fold equity is critical.
M-Ratio (or M-Zone, Harrington's M) measures how many orbits (rounds) you can survive before being blinded out. It's calculated by dividing your stack by the cost of one orbit (small blind + big blind + all antes). It helps determine your optimal tournament strategy.
Green Zone (M>20): Play normally with full range. Yellow Zone (M 10-20): Tighten up, avoid marginal spots. Orange Zone (M 5-10): Push/fold approaching, stop flat-calling. Red Zone (M<5): Pure push/fold mode, never limp or make small raises.
Antes drastically reduce your M-Ratio. With 9 players and a 100 chip ante, that's 900 chips per orbit just in antes. This is why tournament strategy changes significantly when antes kick in - your stack is depleting much faster.
Effective M adjusts your M-Ratio for table size. At a 6-handed table, your M is effectively 50% less because you post blinds more frequently. Effective M = M × (Players at Table / 10). A short-handed table means you need to be more aggressive.
In the Red Zone (M<5), play push/fold poker exclusively. Never limp, never minraise, never flat-call. Look for hands to shove with based on your position and stack. Waiting for premium hands will blind you out - sometimes you need to shove with any ace or king.