How Many Lands Should Your Commander Deck Run?
Use hypergeometric probability to find the right land count for your 99. Data-driven analysis for aggressive, midrange, and control strategies.
- mana base
- strategy
- math
- commander
Every Commander player has asked this question: "How many lands should I run?" The common answer is 37, but that number is a starting point, not a rule. The real answer depends on your deck's mana curve, ramp package, and game plan.
Instead of guessing, we can use **hypergeometric probability** — the same math behind card draw calculations — to figure out exactly how likely you are to hit your land drops on each turn.
The Math Behind Land Drops
In a 99-card Commander deck (excluding your commander), you draw an opening hand of 7 cards, then draw 1 per turn. By turn T, you've seen T + 6 cards total.
The hypergeometric distribution tells us the probability of drawing at least K lands from a deck of N cards when we've seen n cards:
**P(X >= K) = sum of C(K,k) * C(N-K, n-k) / C(N,n) for k = K to min(K_total, n)**
Let's see what this means in practice.
Probability of Hitting Land Drops
This table shows the probability of making every land drop through turn T, for different land counts. "Turn 5 (11 cards)" means you've seen your opening 7 plus 4 draw steps.
| Lands | Turn 3 (9 cards) | Turn 4 (10 cards) | Turn 5 (11 cards) | Turn 6 (12 cards) | Turn 7 (13 cards) |
|---|---|---|---|---|---|
| 33 | 63.2% | 44.1% | 28.0% | 16.3% | 8.8% |
| 35 | 68.1% | 49.8% | 33.4% | 20.7% | 11.9% |
| 36 | 70.4% | 52.7% | 36.2% | 23.1% | 13.7% |
| 37 | 72.7% | 55.5% | 39.1% | 25.6% | 15.6% |
| 38 | 74.8% | 58.3% | 42.0% | 28.2% | 17.7% |
| 40 | 78.8% | 63.6% | 47.9% | 33.7% | 22.3% |
Opening Hand Quality
A keepable hand usually needs 2-4 lands. Here's how land count affects your opening hand:
| Lands | 2+ in opening 7 | 3+ in opening 7 | 0-1 lands (mulligan risk) |
|---|---|---|---|
| 33 | 74.6% | 42.9% | 25.4% |
| 35 | 78.2% | 47.7% | 21.8% |
| 36 | 79.9% | 50.1% | 20.1% |
| 37 | 81.4% | 52.5% | 18.6% |
| 38 | 82.9% | 54.8% | 17.1% |
| 40 | 85.6% | 59.4% | 14.4% |
The Ramp Factor
Mana dorks, signets, and other ramp spells act as pseudo-lands. A Sol Ring on turn 1 is functionally a land drop. When we count lands AND ramp pieces as "mana sources," the math changes significantly.
This table treats lands + ramp as a combined pool of mana sources and calculates the probability of having 4+ mana available by turn 4 (10 cards seen):
| Lands | Ramp Pieces | Effective Sources | P(4 mana by turn 4) |
|---|---|---|---|
| 37 | 8 | 45 | 75.6% |
| 37 | 12 | 49 | 83.3% |
| 37 | 15 | 52 | 87.9% |
| 35 | 10 | 45 | 75.6% |
| 35 | 15 | 50 | 84.9% |
| 33 | 12 | 45 | 75.6% |
| 33 | 15 | 48 | 81.5% |
Recommendations by Strategy
Based on the probabilities above, here are data-driven recommendations:
**Aggressive / Low Curve (avg CMC < 2.5)** - 33-35 lands + 12-15 ramp pieces - You need fewer land drops but fast mana early - Prioritize 1-2 CMC ramp (Sol Ring, Mana Crypt, signets)
**Midrange (avg CMC 2.5-3.5)** - 36-37 lands + 8-12 ramp pieces - The classic 37 works well here - Balance between land drops and spell density
**Control / High Curve (avg CMC > 3.5)** - 37-40 lands + 8-10 ramp pieces - Missing a land drop is devastating - Consider extra land-fetching effects (Cultivate, Kodama's Reach)
**Lands-Matter / Landfall** - 40-44 lands + land-specific ramp - Lands ARE your spells — more is better - Prioritize ramp that puts lands on the battlefield
Key Takeaways
1. **37 lands is a solid default** — it gives you an 82% chance of hitting your 4th land drop on turn 4 2. **Ramp matters more than raw land count** — 35 lands + 15 ramp outperforms 40 lands + 5 ramp for hitting 4 mana by turn 4 3. **Low-curve decks can go lower** — if your average CMC is under 2.5, you can safely cut to 33-34 lands with enough cheap ramp 4. **Don't go below 33 lands** — even with heavy ramp, mulligan rates spike below 33 5. **Use the Leyline deck analyzer** to check your specific deck's mana base probability score
Put this into practice
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