Field guide
Bankroll management
Why survival, sizing discipline, and personal limits matter more than a single opinion.
8 min read · Updated August 2026
01
Separate the bankroll
Only use money set aside for entertainment after essential expenses, savings, and debt obligations. Never borrow to wager, and never treat a model output as income.
02
Use consistent units
A unit creates a stable reference point across different bankroll sizes. Keep it small enough that an ordinary losing streak does not force emotional or financial decisions.
03
Kelly is sensitive
Kelly sizing depends directly on an estimated edge. When the probability estimate is wrong, full Kelly can recommend far too much. Fractional Kelly and hard caps reduce volatility but do not make a bad estimate safe.
04
Set limits before the game
Decide spending and time limits in advance. Do not increase size to chase losses or because a pick is labeled high confidence. Stop if the activity is no longer affordable or enjoyable.