Parlay (Accumulator) Calculator
Add up to 12 legs in decimal or American format. See combined odds, payout, implied probability, total vig and break-even hit rate. Honest math — including why most parlays are bad bets.
How parlays work
A parlay (accumulator, multi-bet, combo) combines multiple individual bets into one. The combined decimal odds are the product of all leg odds:
combined_odds = odds_1 × odds_2 × odds_3 × …
Every single leg must win — if even one loses, the entire parlay loses. The payout is dramatic, but so is the vig.
Why most parlays are bad bets
Bookmakers love parlays for one reason: vig compounds geometrically across legs.
| Parlay legs | Vig per leg | Total vig | Required edge per leg to break even |
|---|---|---|---|
| 1 (single) | 5% | 5% | +5% |
| 2 | 5% | ~10% | +5% |
| 3 | 5% | ~14.3% | +5% |
| 4 | 5% | ~18.5% | +5% |
| 5 | 5% | ~22.6% | +5% |
| 10 | 5% | ~40% | +5% |
The "required edge per leg" is the same — but the cost of being even 1% off compounds. If your probabilities are slightly miscalibrated (and they always are), parlays magnify the error.
When parlays make sense
- Every individual leg is +EV vs the no-vig fair price. Not "feels like a winner" — actually mathematically +EV. If you can't compute EV per leg, don't parlay.
- Correlation play: if two outcomes share underlying causation (e.g. player A wins set 1 AND match), bookmakers sometimes mis-price correlated parlays. Sharps exploit this; casual bettors don't have the data.
- Entertainment / longshot variance: a small recreational stake on a low-probability/big-payout parlay is fine if you accept it as entertainment, not investment.
What TIPERO recommends
TIPERO doesn't publish parlay picks. The model is calibrated for single-bet expected value with Kelly-sized stakes — that's where the publicly tracked profit was built. Parlays are mathematically dominated by single bets in 95%+ of cases. We provide this calculator for transparency, not because we recommend the product.
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How does a parlay calculator work?
Multiplies the decimal odds of every leg to get the combined odds. Combined odds × stake − stake = total profit. All legs must win.
Why are parlays usually bad bets?
Vig compounds across legs. A 4-leg parlay at 5% vig per leg gives ~18.5% total vig — vs ~5% on 4 separate single bets. Same risk, much worse value.
When can a parlay be +EV?
Only if every individual leg is independently +EV at no-vig fair odds. Stacking break-even or −EV legs always produces a −EV parlay regardless of payout.
What's the maximum number of legs?
This calculator supports up to 12. Most bookmakers cap at 10–20 legs and reduce maximum payout above certain thresholds (~€100k).
Does TIPERO publish parlay picks?
No — the model targets single-bet +EV with Kelly sizing. Parlays would magnify probability errors and reduce expected growth.