Lottery Number Generator | 15 Lotteries

This generator produces cryptographically secure random numbers for 15 major international lotteries across Americas, Europe, Nordic, and Oceania. Every draw format is verified against official operator rules — including correct bonus ball pool handling, supplementary number logic, and separate pool draws.

All number generation happens entirely in your browser using window.crypto.getRandomValues() (CSPRNG). No data is sent to any server. Ticket history is stored in your browser's localStorage and persists until you explicitly clear it — closing the tab or browser does not erase your history.

Notable accuracy points: Mega Millions Mega Ball pool is 25 (the correct current format giving 1 in 302,575,350 odds). UK and Irish Lottery Bonus Balls are drawn from the remaining unused numbers — never duplicates of the main draw. La Primitiva's Complementario works the same way; its Reintegro is an independent 0–9 draw. Oz Lotto requires 7 main numbers for Division 1. Finland Lotto (Veikkaus) draws 7 numbers from 1–40 plus a Lisänumero from the remaining 33.

Why Crypto-Secure Randomness Is Used

JavaScript's Math.random() is a pseudorandom number generator (PRNG). It is fast but not cryptographically secure — its internal state can be determined, making its output predictable in theory. This generator uses window.crypto.getRandomValues(), the browser's CSPRNG (cryptographically secure PRNG), which draws entropy from the operating system's hardware noise sources. It is the same API used to generate TLS encryption keys and browser security tokens, approved by NIST SP 800-90A.

What this means practically: the numbers cannot be predicted before or after generation. It does not mean they are more likely to win. Every combination remains equally probable.

Rejection Sampling Eliminates Modulo Bias

A naive "random number in range 1 to n" would compute crypto.getRandomValues() mod n. Because the 32-bit integer range (0 to 4,294,967,295) rarely divides evenly by lottery pool sizes, some numbers would appear very slightly more often. This is modulo bias. This generator discards any value that falls above the largest multiple of the range fitting in 32 bits, then tries again. The average overhead is less than one extra draw per number generated. The result is a perfectly uniform distribution across every pool.

How Bonus Ball and Supplementary Draws Work

Several lotteries draw a bonus number from the same pool as the main numbers, but only from the numbers not already drawn:

UK National Lottery — after 6 main numbers from 1–59, the Bonus Ball comes from the remaining 53. It is used only for second-tier prize (5 + Bonus).

Irish National Lottery — same principle: 6 main from 1–47, Bonus from remaining 41. Second-tier only.

La Primitiva — Complementario drawn from remaining 43 after the main 6. Second-tier only. The Reintegro is an independent draw from 0–9.

Finland Lotto (Veikkaus) — Lisänumero drawn from remaining 33 after the main 7. Second and third tier only.

Oz Lotto / Saturday Lotto — two supplementary numbers drawn from remaining pool. Used for Divisions 2–5 (Oz Lotto) or 3–4 (Saturday Lotto) only.

This generator correctly enforces all these constraints — bonus balls from the remaining pool can never duplicate a main number drawn in the same ticket.

All Combinations Have Equal Probability

A frequently misunderstood point: some numbers appearing more often in recent historical draws does not make them more likely in future draws. Lottery draws are independent events. The probability of any specific number on the next draw is always exactly 1/n (where n is the pool size). A hot number and a cold number have equal probability on every draw. This is not an approximation — it is a mathematical fact that follows from the physical independence of each draw event.

Jackpot Probability Perspective

Powerball (1 in 292M): if one person buys one ticket per draw, they would need on average 292 million draws to win — roughly 2.7 million years at 3 draws per week.

SuperEnalotto (1 in 622M): harder than Powerball by a factor of more than 2. Italy has produced multi-hundred-million-euro jackpots precisely because prizes roll for so long before being won.

Saturday Lotto Australia (1 in 8.1M): the most achievable jackpot of the 15 lotteries here — roughly 36 times easier than Powerball.