# Calculated Odds methodology

Calculated Odds are arithmetic on an operator’s published ticket numbers, which we do not verify. They describe two conditional scenarios for one winning ticket in the main draw. They are not a prediction, a guarantee or a recommendation to enter.

Publisher: Competition Group Ltd
Canonical: https://compapp.co.uk/calculated-odds
Published: 2026-09-24
Sources checked: 2026-09-24
Audience: adults 18+

## Read both figures together

Where your app version offers Calculated Odds, the card and calculator distinguish current sales from a sell-out. Features can differ between app versions. Neither figure establishes the final number of valid entries or verifies how the operator will conduct the draw.

Current sales assumes that the selected tickets are added to the reported sales count and no further entries arrive. At sell-out assumes every ticket in the published allocation becomes a valid entry. The first scenario can change as sales increase; the second uses the published maximum.

The two calculations

| Scenario | Calculation | Assumption |
| --- | --- | --- |
| Current sales | Selected tickets ÷ (reported tickets sold + selected tickets) | No further entries after the selected tickets are added |
| At sell-out | Selected tickets ÷ published total tickets | Every ticket in the published allocation is entered |

## How an amount becomes a ticket count

The default comparison is one ticket. If you enter a GBP amount, we divide it by the listed single-ticket price and round down to whole tickets. We then reduce that count if necessary to fit the reported remaining allocation or a published per-person ticket limit. The calculator shows the ticket count and its actual cost at that price; any remainder is unspent.

For example, £10 at £3 per ticket means three tickets costing £9. If the published limit or remaining allocation is two tickets, the calculation uses two tickets costing £6. An amount below the cost of one ticket produces no calculation.

Bundles, discounts, fees and tickets you already hold are not included. Previous purchases may reduce your remaining allowance. The amount is a comparison input, not a purchase, a recommendation or a spending limit. We do not track purchases with this calculator.

## A worked example

This is a hypothetical example, not a listed competition. Assume a £1 ticket price, 10,000 total tickets, 1,000 reported sales and one winning ticket, with no entry limit restricting the selection.

For £10, the selected count is 10 tickets. Current sales is 10 ÷ (1,000 + 10), or 1 in 101. At sell-out is 10 ÷ 10,000, or 1 in 1,000.

For one ticket, current sales is 1 ÷ (1,000 + 1), or 1 in 1,001, and at sell-out is 1 in 10,000. The extra ticket is included because the comparison represents a hypothetical new entry. It is not a calculation for a ticket already included in the reported sales count.

## What the calculations assume

Every valid entry must have an equal probability of being selected, with one winning ticket selected from that pool. The calculation is per winning ticket in the main draw. It does not calculate the probability of winning any of several prizes, instant wins or different draw mechanisms. We only calculate for listings recorded as a supported single draw; this classification does not independently verify the operator’s rules.

The reported sales count may exclude postal, free or other entries, reservations or adjustments. Additional valid entries missing from that count would reduce the current-sales result. If the final pool is defined differently from the published allocation, the sell-out scenario may not describe it either. Check every entry route and the draw rules with the operator.

We collect published information at intervals. A source-check time records when we read it; it does not mean that the operator’s figures are independently verified or that sales have stopped changing. A listing is not an endorsement.

## When a figure is unavailable

We do not invent a missing denominator. Both figures are unavailable when the published total or sales count is missing or invalid, the currency is not GBP, the price is missing or zero, an entry limit is invalid, the draw type is unsupported, entry is closed or unavailable, no tickets remain, or the amount cannot buy one ticket. A sales count above the published total is invalid.

The current-sales figure also requires a valid sales observation checked within the last 30 minutes. It is withheld for missing or older observations, timestamps more than a minute in the future, a failed source reading, or zero reported sales. Zero reported sales is not presented as a certain win.

When only the current-sales reading fails those extra checks, a calculable sell-out figure can remain alongside an unavailable message and its reason. That is a capacity scenario, not a live-sales figure. When neither scenario can be calculated, the app shows the reason instead of numbers.

## How to read the compact display

A value written as 1:100 means 1 in 100. On compact cards, Full identifies the sell-out scenario; the main figure is the current-sales scenario. The card also shows whether the comparison uses one ticket or a selected amount. Tap the information control for the full figures, source-check time and assumptions.

We round denominators upwards where necessary so rounding does not improve the displayed estimate. Full figures use up to two decimal places for denominators below 10 and whole numbers from 10 upwards. Compact large figures use up to three significant digits: k means thousand, M million, B billion, T trillion and Q quadrillion. The ≈ symbol marks a rounded figure.

For example, an exact denominator of 1,234 may appear as ≈1 in 1.24k on a narrow card. The information sheet displays 1 in 1,234. Rounded figures can look the same even when the underlying calculations differ.

## Use the information without pressure

Fewer tickets sold does not guarantee a win. Do not increase spending to chase a result or recover earlier spending. Not entering is always an option. The Comp App takes no entries and runs no draws; entries take place with independent operators. Our service is for adults aged 18 and over.

If spending or participation feels difficult to control, see [safer-participation support](https://compapp.co.uk/safer-participation). For broader context, read [ticket sales and prize draw numbers](https://compapp.co.uk/guides/ticket-sales-and-odds).

## Method version and corrections

Method version 1, documented 24 September 2026. This page describes the one-ticket and amount calculations, freshness rules and display rounding used by the Calculated Odds feature. We review this page when the method changes.

For a correction, contact [support@competitiongroup.co.uk](mailto:support@competitiongroup.co.uk) with the competition link, the figure, the source-check time and your app version. Do not include payment details. The calculations are our own; the ASA/CAP link below provides general context on claims about winning, not approval of our method.

## Sources and further reading

- [ASA/CAP: claims about chances of winning](https://www.asa.org.uk/advice-online/promotional-marketing-implying-recipients-are-luckier-than-they-are.html)

[Editorial standards and corrections](https://compapp.co.uk/editorial-standards)