House edge in plain numbers: the price of play

House edge in one line

1. House edge

   100% − RTP

2. Theoretical expected loss

   turnover × house edge

   Turnover = stake × number of rounds.

If a game is configured at 98% RTP, the edge is 2%. That is the long-run average share of each staked dollar the model retains — not a tax on your deposit, not a session cap, and not a refund you can claim back later.

The price per 100 units staked

Framing edge as “cost per 100 staked” keeps the units honest. At 2%, the average cost of placing 100 units of turnover is 2 units. At 1,000 units of turnover it is 20 units. At 10,000 units it is 200 units. The edge did not change. The volume did. Every figure below is a long-run average, not a forecast of any session.

Three worked sessions (hypothetical)

Same 98% RTP / 2% edge throughout. Different stakes and round counts — none copied from the calculator or RTP guide pages.

Small session

Stake × rounds

$0.50 × 80 = $40 turnover

Theoretical expected loss

$40 × 2% = $0.80

Eighty cents is the average cost of $40 of stakes at this edge. You might lose $5, break even, or finish up — that is an average, not a forecast.

Medium session

Stake × rounds

$3 × 400 = $1,200 turnover

Theoretical expected loss

$1,200 × 2% = $24

Twenty-four dollars is the average cost of $1,200 of stakes. Check the same arithmetic in the RTP and house-edge calculator with your own inputs. That is an average, not a forecast.

Large session

Stake × rounds

$10 × 1,500 = $15,000 turnover

Theoretical expected loss

$15,000 × 2% = $300

Three hundred dollars is the average cost of $15,000 of turnover at 2%. No stake pattern makes that average disappear; variance only hides it for a while. That is an average, not a forecast.

Edge applies to turnover, not your deposit

Turnover is the sum of stakes. Deposit is the cash you start with. Wins that get staked again add to turnover without adding a new deposit. That is why expected loss can exceed the cash on the table even when the edge looks small: the multiplier is volume of stakes, not balance.

The companion on turnover vs. bankroll: why you can wager 3,000 from a 100 budget walks the split round by round. The lesson here is only which number carries the edge: multiply edge by turnover, then compare expected loss to the cash you can afford to lose — not to turnover itself.

Cost per hour of play (illustrative pace)

If you think in time rather than total rounds, the same edge becomes:

1. Turnover per hour

   stake × rounds per hour

   Rounds per hour is an assumption you choose — not a published casino speed.

2. Theoretical expected loss per hour

   turnover per hour × house edge

Illustrative only: $1 stake, 600 rounds per hour (a fast slot pace you type yourself, not a claim about any game), 2% edge.

Turnover per hour

$1 × 600 = $600

Theoretical expected loss per hour

$600 × 2% = $12

Twelve dollars per hour is a long-run average at that pace and edge — not what any single hour will do. The hourly cost of play calculator keeps stake, rounds per hour, and RTP in one place. That is an average, not a forecast.

What house edge does not tell you

Edge is the centre of the distribution, not the width. Two games at the same RTP can feel completely different in a short session because volatility — hit size and frequency — varies. A low edge does not mean a smooth ride, and a session that felt “lucky” did not repeal the average for the next one. This page does not model variance; it only prices turnover at the edge you assume.

For the RTP definition and why your sample size is tiny compared with certification volume, read RTP is a long-run average — here's what that actually means. For the spread around that average, read volatility: why two 96% games feel completely different. To sanity-check a budget, see budgeting for safer play and the safer-play budget planner — limits, not targets.

A safer-play note

Average cost is a disclosure, not a target spend. Do not raise stakes to “make the edge worth it,” and do not chase losses because the math says you were “due” to lose less. Set money and time limits first, treat any budget as cash you can lose in full, and stop when a limit is hit. Independent help resources are on the responsible gambling page. The sourcing contract for every calculator is on the methodology page. 18+ only.

Frequently asked questions

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