Calculator

Kelly Calculator.

Enter your model's probability, the decimal odds offered, and your bankroll. See full Kelly + 0.5× + 0.25× side-by-side with a hard max-per-bet cap.

Inputs

Your estimated probability of the bet winning. 0.55 = 55%.

Cloudbet/Pinnacle-style decimal odds. 2.00 = even money.

Even if Kelly says size huge, this is the absolute ceiling. Default 2%.

Kelly recommendation

Edge

0%

(p × o) − 1

Full Kelly

0%

≈ $0 stake

0.5× Kelly

0%

≈ $0 stake

0.25× Kelly (recommended)

0%

≈ $0 stake (after cap)

Hard cap clamps every recommendation at $200 (2% of bankroll).

Embed on your site

Free to embed on agency comparison pages, blog posts, and SaaS evaluation guides. Just copy the snippet — there's no API key, no rate limit, and the calculator stays current as we update model pricing.

HTML embed 
<iframe src="https://edge.glitchexecutor.com/tools/kelly-calculator?embed=1" width="100%" height="780" style="border:0;border-radius:12px;max-width:760px;" loading="lazy" title="Kelly Calculator — Glitch Edge — by Glitch Grow"></iframe>
<p><small>Free tool by <a href="https://edge.glitchexecutor.com">Glitch Grow</a> — buy-once AI agent stacks for agencies.</small></p>

By embedding you agree to keep the credit link visible. We use it as a backlink signal — it's the deal that lets us keep the calculator free.

Frequently asked questions

  • What is the Kelly criterion?

    Kelly is a formula for sizing bets to maximize long-run bankroll growth. The full-Kelly formula is f* = (p × o − 1) / (o − 1), where p is your model probability and o is the decimal odds. See the glossary entry for the full math.

  • Why use fractional Kelly instead of full Kelly?

    Full Kelly has brutal variance — 50%+ drawdowns are common even on a real edge. Fractional Kelly (typically 0.25× or 0.5×) trades some long-run growth for survivable variance. Most professional bankrolls run between 0.25× and 0.5×.

  • What if my model probability is wrong?

    That's the main risk. A 5%-overestimated edge translates to oversizing relative to the actual Kelly fraction. Hard caps (the max-per-bet input here) are your second line of defense — even if Kelly says size huge, the cap clips you.

  • Does Glitch Edge enforce Kelly fractions automatically?

    Yes — every strategy on the platform uses configurable fractional Kelly with a hard cap, refuses to size above 1× regardless of operator config, and halts on drawdown breach. See Glitch Edge if you want this enforced in code, not just calculated.