The doubled ledger is this market’s default price

Ask any shelf of casino welcome pages what a fair opening offer looks like and the answers converge on one shape: your deposit, matched once, with a clock attached. The 100% deposit bonus is the line everything else gets measured against. British baseline rows print it at modest ceilings with licensed protections standing behind it; the offshore end prints the same shape with taller percentages, bigger lids and heavier multipliers. Either way the working parts do not change: money in, money matched, a turnover requirement, a cap, and a minimum deposit that opens the cashier.

The offer shelf sorts the double into five shapes, and the model needs a figure for each, so every line below carries its assumption in the open.

1. The straight double. A 100% match with a ceiling in the £50 to £150 band and nothing bolted on. The model takes a 35-times clock on the bonus, because that is the multiplier this part of the market asks for more often than any other.
2. The double with spins. The same match with a bundle of 50 to 100 spins attached. Spins carry their own small term, so the model prices the match first and treats the bundle as a separate line, never as a reason to accept a heavier multiplier.
3. The capped double. A 100% match with a lid, set at £250 in this page’s model. Past the lid the deposit still plays; it simply stops earning match, and the ledger marks that boundary in plain pounds so nobody discovers it at the cashier.
4. The crypto double. Offshore, the percentage climbs to 100 to 250 per cent where crypto rails carry the payment, with ceilings that reach £1,000 to £2,000 and payouts that can clear in hours. The ledger shape is unchanged; the payout line and the lid move.
5. The staged double. The percentage rises with the deposit tier, from 100 per cent at the floor toward 250 at the top of the scale. The model treats each tier as its own small ledger, because the multiplier attaches to whichever tier the deposit lands on.

Five shapes, one instrument. Whatever the banner shouts, the arithmetic reduces to a handful of numbers: the match, the clock, the lid and the minimum. The rest of this page itemises them at deposit sizes readers actually search for.

The ledger itemised at £100

Round numbers make the honest chart, so the model starts at £100 deposited. Three bars follow, and all three share one unit, pounds per £100. The match value bar adds 100, the doubling itself, credited as bonus funds. The wagering bar carries 350, the modelled clock the terms start the moment the bonus lands. The cap bar prints at 250, the lid where the doubling stops regardless of deposit. Read together, the bars describe a transaction, not a gift.

The proportions carry the argument. The wagering bar stands at three and a half times the height of the match bar, which is why a doubled balance reads more honestly as a rental of play than as free money. The cap bar sits between the two: tall enough to cover this deposit whole, low enough that a larger deposit would run into it and stop earning match. A chart drawn this way answers the question banners avoid: what does the word double cost, per £100, before a single spin decides anything.

The unit matters as much as the bars. Everything above is modelled per £100 of deposit, category-typical rather than quoted from any single promotion, and the caption keeps that framing pinned. At other deposit sizes the picture shifts: smaller deposits clear under the lid with room to spare, larger ones press against it. The worked example below takes the deposit down to £50, where the sum fits in a sentence.

The worked sum at £50

The calculator runs the four numbers this page is built on: a £50 deposit, a 100% match, a 35-times multiplier and a £250 cap. Change any input and the ledger recalculates on the spot, which is the point of showing the working rather than a verdict.

Take the inputs one at a time. A £50 deposit at 100% earns a £50 match, so £100 sits in the balance, half cash and half bonus. The multiplier attaches to the bonus, not the balance: 35 times £50 sets the clock at £1,750 of turnover. The cap does nothing at this size, because a £50 match sits far below the £250 lid; the same offer at a £300 deposit would meet the lid and stop doubling at £250 of bonus.

The readout that matters most is the one banners never print: the expected cost of carrying the clock, stated in pounds. Turnover is not a neutral abstraction. Staked money meets the house edge on every round, so a £1,750 clock has a price even before any single session wins or loses, and the calculator prints that price on the assumptions shown. This is what presenting a bonus honestly looks like in practice: the cost sits next to the promise, in the same font, at the same time.

Scale the habit, not just the sum. Double the deposit and the match doubles, but the clock doubles with it, because the multiplier rides on the bonus. That proportion is the quiet argument of this page: the doubled ledger grows in a straight line, so the deposit that fits a budget and a calendar matters more than the percentage on the banner.

When the doubled ledger is the honest pick

A short clock beats a loud percentage more often than the banners admit, and the model shows it in one line each. A £50 deposit under a 100% match at 35 times the bonus carries a £1,750 clock. The same deposit under a 200% match at 45 times carries a £4,500 clock, because the bonus has doubled and the multiplier has climbed with it. The modest double asks for £2,750 less play to reach the same withdrawable finish.

Climb the ladder and the gap widens. At 300%, the match on £50 is £150, and a 40-times term sets the clock at £6,000. At 400% on the same 40-times assumption, it reads £8,000. These are the page’s own figures on stated assumptions, not quotes from any operator, and they exist to make one point: percentage and multiplier compound, and the clock grows faster than the headline suggests. A player with ten hours a month should price the clock before the percentage, every time.

The lid is the second test. Where a market-typical cap sits at £1,000, the deposit that earns it whole is the last deposit the percentage rewards; money past that line adds play but no match. A 400% headline with a low lid can therefore be worth less in matched pounds than a 100% headline with a lid you will never meet. Check the cap before the percentage, which is the order the ledger uses.

The third test is practical: can the clock be cleared inside the time the terms allow, on games you would open anyway, under a maximum stake that keeps the bonus intact? A short, plain double on familiar games is easier to carry than a tall one on games you would not otherwise touch. Payout windows belong in the same test, because winnings you cannot reach for days are a promise with a delay printed on it.

Finally, the honest pick has a licence dimension. Baseline rows print the double at British terms: smaller ceilings, regulated protections, payouts inside a few banking days. Offshore rows print taller percentages and bigger lids, with the trade-offs the licence note below lists in full. The ledger prices both shapes the same way; the licence note prices what the ledger cannot.

How the field prints the same ledger

The table gathers the double across the pool this site tracks: baseline rows first, offshore rows after. Ranges are category-typical, compiled from operator-published terms, and they describe offers of this kind rather than quoting any single promotion. Read the wagering column before the welcome column; that ordering is the method of this page in miniature.

Figures are category-typical ranges compiled from operator-published terms at the time of writing, not quotes of any single promotion. UKGC-licensed rows are the British baseline shown for comparison; none of them are claimable at the offshore offers modelled on this page. Verify every term on the operator’s own page before you take it.

The ledger, line by line

The registry below pins the worked example to five lines so the sum can be checked without reopening the calculator. Each line carries the value the model produces and a comment on what the line actually buys.

Any line that looks generous can be tested by changing the inputs above, and any line that looks harsh can be tested the same way. A ledger that recalculates is a model; one that cannot is a slogan.

The honesty rule the advertising code already writes

Gambling advertising in the UK is governed by the CAP Code, administered by the Advertising Standards Authority, and the code’s rules reach both the protection of minors and the honest presentation of bonuses. This page borrows that standard for its own arithmetic: the match, the clock, the lid and the expected cost are printed together, because a bonus presented honestly is one whose price is visible beside its promise. The offshore rows in the table hold no UK Gambling Commission licence, so the code’s complaint route does not stand behind those offers the way it stands behind a licensed one, and the licence note beside this paragraph keeps that difference on the record. Nothing here predicts an outcome, and that is the point: a ledger itemises costs, and costs are the only part of a bonus a comparison page can state honestly.