Kelly Criterion for Crypto Bots 2026: Optimal Position Sizing Guide
The Formula That Maximizes Growth
The Kelly Criterion answers the most important question in trading: how much should I risk per position? Too little = slow growth. Too much = ruin. Kelly gives the mathematically optimal answer — and most bot traders have never heard of it.
Size your bots correctly — 3Commas free plan---
The Formula (Simplified)
Start Automating Your Crypto Profits Today
Join 1.2M+ traders earning passive income with 3Commas bots. Setup in 5 minutes.
Start Free Trial
Where:
- W = win rate (e.g., 0.70 for 70%)
- R = win/loss ratio (avg win ÷ avg loss)
Example Calculation
Your DCA bot stats: 72% win rate, average win +2%, average loss -8% (R = 0.25)
Kelly % = 0.72 − [(0.28) / 0.25] = 0.72 − 1.12 = -0.40
Negative Kelly = the strategy loses long-term at current parameters. This is why stop-loss discipline matters — a 72% win rate can't survive losses 4x larger than wins.
A Winning Example
Stats: 65% win rate, avg win +3%, avg loss -3% (R = 1.0)
Kelly % = 0.65 − [0.35 / 1.0] = 0.30 → bet 30% of capital per position
---
Kelly Applied to Bot Capital Allocation
The Real Use Case
Kelly isn't for individual trades — it's for how much of your portfolio each bot should control:
| Bot | Win Rate | Avg Win | Avg Loss | Kelly % | Allocation |
|---|---|---|---|---|---|
| BTC DCA | 74% | +2.5% | -6% | 0.31 | 31% |
| ETH DCA | 71% | +2.2% | -5.5% | 0.28 | 28% |
| SOL DCA | 66% | +3.5% | -9% | 0.24 | 24% |
| Alt grid | 68% | +1.8% | -4% | 0.38 | 38% |
Wait — these sum over 100%. Kelly assumes independent bets; for simultaneous bots, scale down proportionally or use fractional Kelly.
---
Why Full Kelly Is Dangerous
Full Kelly maximizes long-term growth but with brutal drawdowns — 50%+ portfolio drops are normal at full Kelly sizing. Professional traders use fractional Kelly:
| Kelly Fraction | Growth Rate | Max Drawdown | Best For |
|---|---|---|---|
| Full (1.0x) | 100% optimal | 50-70% | Nobody, honestly |
| Half (0.5x) | ~75% of optimal | 25-35% | Aggressive pros |
| Quarter (0.25x) | ~50% of optimal | 12-18% | **Recommended** |
| Eighth (0.125x) | ~30% of optimal | 6-10% | Conservative |
---
Calculating Your Bot's Kelly Number
Step 1: Gather 90 Days of Stats
From your 3Commas bot history:
- Win rate: winning deals ÷ total deals
- Average win: total profit ÷ winning deals
- Average loss: total loss ÷ losing deals
Step 2: Apply the Formula
| Your Stats | Kelly % | Quarter-Kelly |
|---|---|---|
| 70% WR, 2% win, 5% loss | 0.20 | 5% per bot |
| 75% WR, 2% win, 4% loss | 0.38 | 9.5% per bot |
| 60% WR, 3% win, 4% loss | 0.30 | 7.5% per bot |
| 80% WR, 1.5% win, 6% loss | 0.30 | 7.5% per bot |
Step 3: Rebalance Quarterly
Stats drift — recalculate Kelly every 90 days and rebalance allocations. Bots with improving stats earn more capital; degrading ones get cut.
---
Kelly vs Common Sizing Methods
| Method | Logic | Weakness |
|---|---|---|
| Equal split | 5 bots = 20% each | Ignores performance differences |
| Fixed % | Always 10% per bot | No adaptation |
| Kelly | Math-optimal | Needs accurate stats |
| Quarter-Kelly | Math-optimal, safer | Slightly slower growth |
| Gut feel | Whatever feels right | Usually wrong |
---
The Kelly-Powered Portfolio
| Bot | Quarter-Kelly % | Role |
|---|---|---|
| BTC DCA | 8% | Core |
| ETH DCA | 7% | Core |
| Stablecoin grid | 10% | Safety layer |
| SOL DCA | 6% | Growth |
| Alt basket | 5% | Speculation |
| **Deployed** | **36%** | — |
| **Reserve** | **64%** | Dry powder |
---
FAQ
Q: What is the Kelly Criterion in simple terms?
A: A formula that calculates the optimal percentage of capital to risk based on your win rate and win/loss ratio. It maximizes long-term growth while avoiding ruin — the same math pros and casinos use.
Q: How do I use Kelly for crypto bots?
A: Calculate each bot's win rate and average win/loss from 90 days of history, apply the formula, then use quarter-Kelly (divide by 4) for the actual allocation. Rebalance quarterly as stats update.
Q: Why not use full Kelly?
A: Full Kelly produces 50-70% drawdowns — mathematically optimal but psychologically unbearable. Quarter-Kelly captures ~50% of the growth with ~25% of the pain. Every pro uses fractional Kelly.
Q: What if my Kelly calculation is negative?
A: Your strategy loses long-term — the math is telling you to stop or fix parameters. Usually means losses are too large relative to wins: tighten stop losses or widen take profits.
Q: How often should I recalculate Kelly?
A: Every 90 days minimum, or after any major market regime change. Bot stats drift — a strategy with 75% win rate in a bull market might drop to 55% in a bear, changing its optimal allocation.
---
Final Verdict
The Kelly Criterion transforms bot allocation from guesswork into math: measure your stats, calculate optimal sizing, apply quarter-Kelly, rebalance quarterly. Most traders over-allocate to their worst bots and under-allocate to their best. Kelly fixes that — and the difference compounds massively over time.
Size your bots like a pro — 3Commas free