An offer is worth what its terms let you keep, and the number in the headline rarely decides that.
That is the first thing to check in any offer, here or anywhere else. Money you can take out at once is worth its full amount; winnings paid as bonus funds behind a turnover requirement are worth a fraction of it until the requirement is met. The rest tells you whether the requirement is reachable at all: the minimum odds that filter which tickets count, the expiry window, and which games contribute to the turnover.
Since campaigns change regularly, today's amounts and dates are whatever the operator's promotions page says. The guides below cover how to read an offer, not what happens to be live.