What it means
Bang on means exactly right or perfectly accurate, no wiggle room. People use it for guesses, directions, prices, timings, anything that lands dead centre. It can also mean precisely on time, like a train arriving bang on six. Sounds punchy because bang works as an intensifier, so you're basically saying it hit the target.
Usage examples
"You said the bus would rock up at ten past, and it did. That call was bang on, mate, even my nan’s impressed."
"Your estimate was bang on, the bill came to exactly what you said."
"The train was bang on time for once, not a minute late."
Where it comes from
Bang here means exactly, precisely, square on the target, the way a dart lands bang in the bullseye. So something bang on is spot on, perfectly accurate or right on time, with no margin of error. The bang carries that satisfying sense of hitting the mark cleanly and dead centre.
Other ways to say it
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