Rex says
The fast lane for the math you almost remember from school. Type the numbers, get the answer, move on with your day.
Try a scenario
Click to load — tweak from there.Inputs
Result
Total combinations
6
Total amount risked
$60.00
Payout for each winning combo
$36.45
Best-case payout (all picks win)
$72.89
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter total number of picks.
- 2Enter round robin by (legs per combo).
- 3Enter average odds per leg (american).
- 4Enter stake per combination ($).
- 5Read your total combinations on the right — it updates as you type.
- 6Hit Share to keep the scenario or send it to someone.
About this calculator
A round robin splits a set of picks into every possible smaller parlay combination — for example, 4 teams played as round robin by 2s creates six separate 2-team parlays instead of one 4-team parlay. This spreads your risk: instead of needing all four legs to hit for any payout, you can hit some combinations and still profit, at the cost of needing a larger total stake since you're now funding multiple parlay tickets instead of one. This calculator takes your number of picks, the combo size you want to round robin by, a per-combo stake, and average odds per leg, then computes the total number of combinations (using combinatorics), total amount risked, and a rough payout scenario if a specific number of your legs win. Round robins trade a lower maximum payout (versus the single full parlay) for a meaningfully higher chance of a partial cash return, which is why they're popular with bettors who like multi-leg tickets but want to avoid an all-or-nothing outcome.
Worked example
Using the values the calculator loads with:
Inputs
- Total number of picks: 4
- Round robin by (legs per combo): 2
- Average odds per leg (American): -110
- Stake per combination: 10 $
Results
- Total combinations: 6
- Total amount risked: $60.00
- Payout for each winning combo: $36.45
- Best-case payout (all picks win): $72.89
What each field means
Inputs
- Total number of picks
- The total number of picks used in the calculation. Starts at 4 so you have a working example on load. Accepted range: 3–8.
- Round robin by (legs per combo)
- The round robin by (legs per combo) used in the calculation. Starts at 2 so you have a working example on load. Accepted range: 2–7.
- Average odds per leg (American)
- The average odds per leg (american) used in the calculation. Starts at -110 so you have a working example on load.
- Stake per combination ($)
- The stake per combination used in the calculation, measured in $. Starts at 10 $ so you have a working example on load.
Results
- Total combinations
- Returned as a whole number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total amount risked
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Payout for each winning combo
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Best-case payout (all picks win)
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How many combinations does a 4-team round robin by 2s create?
C(4,2) = 6 separate 2-team parlays: every unique pair among your four picks. If you round robin the same four picks by 3s instead, you get C(4,3) = 4 combinations of 3-team parlays, each requiring three of your four legs to hit for that specific ticket to pay.
Why would I round robin instead of just betting one big parlay?
A single 4-team parlay pays more if everything hits, but pays zero if even one leg loses. A round robin by 2s still profits if you go 3-1 or better in some combinations, trading a smaller maximum payout for meaningfully lower variance and a real chance at partial profit even with one loss.
Does a round robin cost more than a straight parlay?
Yes, proportional to the number of combinations. If you stake $10 per combo and round robin 4 picks by 2s (6 combos), you're risking $60 total, not $10 — factor that into your bankroll before placing it, since it's easy to underestimate total risk when focusing on the per-combo stake.
Accuracy and limitations
- Results are rounded for display; the underlying calculation keeps full precision.
- Very large or very small inputs may hit floating-point limits in the browser.
- Inputs outside the accepted range are clamped rather than rejected.
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Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Round Robin Parlay Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/round-robin-parlay-calculator
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/round-robin-parlay-calculator" target="_blank" rel="noopener">Round Robin Parlay Calculator — RevenueLab</a> (2026).</p>
Source: [Round Robin Parlay Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/round-robin-parlay-calculator) (2026).