Quick answer: A betting unit is a standardized percentage of your bankroll, typically 1-2%, used as the base wager amount. Pros track profit and loss in units rather than dollars because units make results comparable across different bankroll sizes. A $50 bettor and a $5,000 bettor can both report ‘5 units of profit this month’ to communicate the same level of performance. Most professional handicappers report results in units for this reason.
How Units Standardize Performance
If a bettor reports ‘+12 units over the past 100 bets,’ that translates to 12% of one unit’s bankroll allocation. With 1% units, that’s 12% bankroll growth. With 2% units, that’s 24% growth. The actual dollar amount depends on bankroll size, but the percentage tells you everything you need to know about the bettor’s edge. PropsBot.AI’s Aggregate ROI of ~27.8% across 218,826 graded props translates roughly to +60,000 units profit at 1% sizing, which is the kind of compounding that defines sharp betting.
What’s a Reasonable Unit Size
Most sharp bettors use 1-2% per single bet. Quarter Kelly sizing typically falls in this range for moderate-edge bets. Beginners often start at 1% to limit downside. Professional bettors with strong models can stretch to 3-5% on high-confidence plays, but going higher is gambling, not investing. The general rule: if a single bad streak can ruin your ability to keep betting, your units are too large.
Why Most Public Bettors Get Unit Sizing Wrong
Public bettors typically bet 5-15% per game without realizing it, because they lack systematic sizing. A bettor with a $1,000 bankroll who places $100 on a game is at 10% per bet. A losing run of 3-4 in a row puts them in massive drawdown. The math says even +EV bettors lose 4 in a row regularly due to variance, so any system that can’t survive a 4-bet loss streak isn’t sustainable. Quarter Kelly or 1-2% flat units survive that stress test comfortably.
Tracking Units Properly
Spreadsheet your bets with stake size in units (1u, 0.5u, 1.5u for higher confidence). Track running profit in units, not dollars. Recalculate unit size monthly based on bankroll changes (so a 20% bankroll growth doesn’t leave you under-betting against the new total). The PropsBot performance dashboard tracks results this way: +60,778 units of cumulative profit across 218,826 graded props, broken down by signal type and sport. That’s the kind of unit-level transparency that makes a track record verifiable.
Frequently Asked Questions
How big should a unit be?
Most sharp bettors use 1-2% of bankroll per unit. Conservative starts at 1%, aggressive at 2%. Going above 3% creates ruin risk during normal variance streaks.
Why do pros track units instead of dollars?
Units standardize performance across bankroll sizes. A +50 unit profit is the same percentage gain whether the bankroll is $1,000 or $1 million. Dollars don’t communicate the relative performance.
How do I size units for different confidence levels?
Half-unit (0.5u) for low-confidence bets, full unit (1u) for normal plays, 1.5u or 2u for highest-confidence bets. Anything above 2u should be rare and only on bets with measurable model edge.
When should I recalculate unit size?
Monthly is standard. After any large bankroll swing (up or down 20%+), recalculate to keep unit percentage consistent.
What does +50 units profit really mean?
Profit equal to 50 times your unit size. At 1% units, that’s 50% bankroll growth. At 2% units, 100% bankroll growth. The percentage depends on your unit allocation.
Part of the PropsBot.AI Sports Betting Glossary. Updated 2026-05-04.
