Lottery Odds Calculator

How to use

1. 1Click a preset chip to load a real lottery format (Powerball, Mega Millions, UK Lotto, EuroMillions, EuroJackpot, Lotto 6/49, SuperEnalotto, El Gordo, Australian Saturday Lotto).
2. 2Or set a custom format: main pool size, numbers you pick per ticket, optional bonus pool size, and bonus picks per ticket. Use 0 for the bonus pool if your lottery has none.
3. 3Read the jackpot odds, the total number of distinct possible tickets, and the chance of matching at least one main number in the headline cards.
4. 4Scroll the tier table for the exact probability and 1 in N odds of every match count, with and without the bonus when a bonus pool is in play.
5. 5Optional: enter the number of tickets you plan to buy to see the cumulative probability of winning the jackpot at least once.
6. 6Optional: click Add prize amounts, type the cash prize for each tier, and set the ticket price to compute expected net value per ticket and the probability of winning any prize.
7. 7Click Copy summary to grab the full result as plain text, or Reset to start over.

About this tool

Lottery Odds Calculator turns any pick-N-of-M lottery format into a complete probability table: jackpot odds, every prize tier from matching all main numbers down to matching none, the chance of hitting at least one main number, the cumulative probability of winning any prize at the amounts you set, and the expected net value per ticket once a ticket price is provided. Pick a preset (US Powerball 5 of 69 plus 1 of 26, Mega Millions 5 of 70 plus 1 of 24, UK National Lottery 6 of 59, EuroMillions and EuroJackpot 5 of 50 plus 2 of 12, Lotto 6/49, Italian SuperEnalotto 6 of 90, Spanish El Gordo de la Primitiva 5 of 54 plus 1 of 10, Australian Saturday Lotto 6 of 45) or type a custom format using main pool size, picks per ticket, bonus pool size, and bonus picks. The math is the standard hypergeometric distribution: the chance of matching exactly k of your r picks against m drawn numbers is C(r, k) times C(m minus r, r minus k) divided by C(m, r), with bonus matches modelled independently using the same formula on the second pool. Every binomial coefficient is computed in BigInt so Powerball-class numbers like C(69, 5) times C(26, 1) equal 292,201,338 exactly, with no floating-point rounding. The tier table sorts from best outcome to worst and shows odds as a clean 1 in N value, the raw decimal probability, and the percentage; very small percentages render in scientific form (3.42 x 10^-7 %) instead of unhelpful strings of zeros. Two optional inputs unlock deeper analysis: enter a number of tickets purchased to see the probability of hitting the jackpot at least once across independent tickets (computed with 1 minus (1 minus p) to the N using log1p for numerical safety), and add a prize amount for each tier together with a ticket price to read the expected value per ticket (sum of prize times probability minus the ticket price). Use this to size up a lottery before you spend, to teach hypergeometric probability with a topical example, to check published odds against the math, to compare formats from different countries side by side, or to make peace with the fact that buying 100 Powerball tickets still leaves the chance at roughly 1 in 2.9 million. Everything runs locally in your browser; the numbers you enter stay on your device. This calculator describes probabilities; it does not predict draws and is not gambling advice.

Free to use. Works in your browser. No signup, no login.