PredictionsHQ
Three countries share a language and almost nothing else that matters here, so every table on this site says which one it is about before it says anything else.

Predictions HQ

Betting calculators

Return calculator

This page gives the arithmetic rather than a widget, and the arithmetic is short enough to do on a phone keypad. A decimal price already includes the stake, so the return is stake multiplied by price, and the profit is that minus the stake. Two thousand naira at 2.40 returns 4,800 and profits 2,800.

The reason to do it before rather than after is that the same sum tells you what a losing run costs. Ten bets of that size is twenty thousand naira at risk, and no run of prices changes that figure.

Accumulator calculator

Multiply the prices, then multiply by the stake. Four selections at 1.50, 1.80, 2.10 and 1.40 give 1.50 times 1.80 times 2.10 times 1.40, which is about 7.94, so a hundred cedis returns roughly 794.

The part worth understanding is what happens to the margin. A bookmaker's hold applies to each leg, so a four-fold compounds four holds rather than one. That is why accumulators are promoted hardest and priced worst, on all three of these markets.

Implied probability

Divide one by the decimal price and you have what the price implies. A price of 2.40 implies about 41.7 per cent; a price of 1.40 implies about 71.4 per cent.

Add the implied probabilities of every outcome in a market and the total tells you the hold. A three-way market priced at 1.85, 3.60 and 4.20 gives roughly 0.541, 0.278 and 0.238, which total about 1.056. That book is holding close to 5.6 per cent before anything about the result is known. For comparison, the one operator whose margin has been computed here from its own feed, SportyBet Ghana, ran between 1.9 and 2.3 per cent across 491 football matches.

Staking calculator

The only staking rule that survives contact with a bad month is a flat fraction of a fixed bankroll, decided in advance. Pick a figure you would not mind losing entirely, then stake a small constant share of it, and recalculate that share on a schedule rather than after a result.

Anything that raises the stake because the last one lost is a system for turning a normal losing run into a serious one. There is no arithmetic on this page that makes it work, because there is none.