How long does it take for nuclear radiation to kill you from a nuke?

Answer 1

If high enough dose, you might last a week, but you'd be wishing you were already dead. Whether it's a fatal dose or not though depends both on total accumulated dose and time frame over which it was received. A fatal dose of 550 R (for 50%+), received in under a week, if spread out more evenly over four months would be survivable for most healthy adults. Nuclear bomb blasts & fallout are more survivable than most think, IF one knows what to do beforehand. Of course, those at ground zero are toast, but the overwhelming majority of the potential casualties are further out in the blast zone and further downwind in the fallout zone later and, IF they know what to do, 90% of them can save themselves. More details here GoodNewsNuke.com

Answer 2

The effects of nuclear radiation can vary depending on the dose and proximity to the explosion. Acute radiation sickness can develop within hours to days, leading to severe health consequences and potentially death. Prolonged exposure to high levels of radiation can also increase the risk of developing cancer in the long term.