Start with the wagering base

A "30x" requirement means you must place bets totalling thirty times an amount before bonus winnings can be withdrawn. The amount is the whole question. Applied to the bonus only, a 100 dollar bonus needs 3,000 dollars of qualifying bets. Applied to the deposit plus the bonus, the same offer needs 6,000. The terms say which, usually in one clause near the end.

A worked example, not a live offer

Deposit 100, receive a 100 bonus, 30x wagering. Bonus-only base: 3,000 in bets. Deposit-plus-bonus base: 6,000 in bets. At a game with a 3 percent house edge, the expected cost of 6,000 in bets is around 180, which is more than the bonus. At a 1 percent edge it is around 60. Neither figure is a promise; you can lose the whole balance long before the requirement is met.

Then the weightings and the limits

Game contributions
Slots often count 100 percent towards wagering, table games and live dealer games far less, and some games zero. A requirement that looks achievable on slots can be impossible on blackjack.
Maximum bet
Most bonus terms cap the stake while a bonus is active. Exceeding it, even once, is a common reason for winnings to be voided.
Expiry
The requirement usually has to be met within a fixed number of days. Unfinished wagering forfeits the bonus and often its winnings.
Withdrawal cap
Some terms cap how much can be withdrawn from bonus winnings, regardless of how much was won.
Withdrawing early
Requesting a withdrawal with an active bonus usually cancels the bonus and any winnings from it. Craze's FAQ says a request that is not covered by real funds is declined.

The crypto difference: rewards, not welcome bonuses

Crypto casinos compete less on welcome bonuses than on rewards schemes that return a share of every bet: rakeback, reloads, level-up rewards and VIP tiers. These are easier to value than a welcome bonus because they are paid on turnover you would have wagered anyway, but they are also where the marketing is loosest. A "50 percent rakeback" claim is 50 percent of something, and the something is usually the house edge on your bets, not your stake. Stake's affiliate help page, describing its own commission, makes the same point: the percentage is applied to house edge, not to wagers. Each review records the rewards scheme as the operator documents it, without putting a value on it.

Not every casino has an offer to read. Craze's FAQ, at the check date, says bonuses and promotions are coming and that users will be told when they launch. Gamdom's FAQ says it has no traditional bonuses at all; its public welcome offer is a rakeback boost to 15 percent for the first week, and the rate it pays afterwards is personalised and not published. Shuffle documents its rakeback at 5 percent of house edge, which on a game with a 2 percent edge is a tenth of a cent per dollar wagered. Stake's is 3.5 percent of house edge, and its welcome offer is simply early access to that rakeback for entering a referral code; no deposit match is documented.

Bonus abuse clauses

Every set of terms reviewed here allows the operator to void bonus winnings for what it calls abuse: multiple accounts, betting patterns designed to clear wagering with minimal risk, or claiming an offer that was not open to your country or account. The clauses are broad and the operator decides. If you take a bonus, play it as an ordinary player would, keep to one account and keep a copy of the terms as they stood when you opted in.

Choosing no bonus

Declining a bonus is a legitimate choice, and at some casinos it is the better one: a deposit without a bonus is not locked to a wagering requirement, is not subject to a maximum bet, and can be withdrawn under the ordinary rules. If the terms are unclear or the requirement pushes you to bet more than you planned, do not opt in.