How we calculate odds & value score

Every number on CarRaffleOdds — odds, value score, expected value — is calculated from the same scraped data: ticket price, total tickets in the draw, tickets already sold, and the stated prize value or cash alternative. Here's exactly what the numbers mean and how they're worked out.

Real odds

The headline odds on a fixed-ticket draw are simple: one ticket, one entry into a draw with a capped number of tickets. If a competition has 10,000 tickets, your odds with one ticket are 1 in 10,000.

But most draws aren't sold out — and that matters. A guaranteed draw on a set date with only 4,000 of 10,000 tickets sold means your actual odds are 1 in 4,000, not 1 in 10,000. We show odds based on the ticket cap (the worst case), but the sold percentage lets you spot the undersold draws where your real odds are meaningfully better.

Spot-the-ball competitions (like BOTB's flagship) have no fixed ticket cap — odds depend on how many entries are submitted, which varies. We don't show a "1 in X" figure for those.

Value score

The value score answers the question: how much prize value are you buying per £1 you spend? It's the single most useful number for comparing draws of different sizes and ticket prices.

A raw score of 1.0 means the prize is worth exactly as much as the total ticket revenue if every ticket sells — perfect value, in theory. In practice, most draws sit below 1.0 (the operator needs margin). Higher is better.

We display this on a 0–100 scale using a square-root curve, which spreads scores more evenly and stops outliers dominating:

Where a cash alternative is stated but no prize value is given, we use the cash alternative as a conservative proxy. When neither is available, value score shows "—".

Prize value

We use the prize value or cash alternative as stated by the operator on their own page — we don't independently value the car. If an operator claims a car is worth £45,000, that's what goes into the formula.

Worth checking: the cash alternative (usually 60–80% of the stated car value) is often a more honest indicator of what the prize is actually worth to a winner who takes the money.

Data freshness

Ticket counts and sold percentages are scraped from the operator sites and updated throughout the day. End dates come from the operators directly. We don't guarantee real-time accuracy — always verify on the operator's site before entering.

Draws that have passed their stated end date are automatically marked as drawn and removed from live listings.