Enter your last cigarette and see which of six phases you are in, from the first six hours out to a month and beyond. The hardest stretch is 24 to 72 hours — and the useful thing about that is how short it is, because nicotine is effectively cleared by hour seventy-two and the intensity comes down from there.
One subtraction, then a lookup. The page takes the time of your last cigarette away from now, and the phase you are shown is whichever phase's window contains that elapsed figure. The windows are 0 to 6 hours, 6 to 24, 24 to 72, 3 to 7 days, 1 to 4 weeks, and 1 month onward with no end. Nothing about your body is read; the clock decides which paragraph you see.
The bar beside each phase carries an intensity value — 40, then 70, then 100 at the 24-to-72-hour peak, then 65, and down from there. Those numbers are OURS. They are not a scale anybody publishes, not a score, and not a prediction of how you will feel: they are a shape drawn so the page can say out loud which phase is the hardest, which is the one useful thing a timeline of this kind can do. Read them as a picture of the ordering, not as units.
The phase boundaries themselves come from the pharmacology the page already names: nicotine's plasma half-life averages about two hours and cotinine's about sixteen, so nicotine is substantially gone within a day and effectively cleared by seventy-two hours. That is why the peak sits where it sits. The symptom lists per phase are the ones cessation services publish; nothing here is a diagnosis, and a page cannot tell the difference between withdrawal and something that needs a doctor.
Your last-cigarette time lives in this browser only, and the timeline runs off your device clock. Nobody is holding a second copy.
Nothing on this page is medically reviewed and nothing above measures anything about you — it explains a calculation. Where a number here is our own judgement rather than a published figure, the note says so and cites nothing; where the health bodies disagree, it carries the disagreement. Method last checked 21 August 2026.
Nicotine withdrawal has two distinct components. Physical withdrawal — driven by receptor hypersensitivity and neurochemical adjustment — is most intense during the first 72 hours and substantially resolves within 2–4 weeks. Psychological withdrawal — triggered by habits, stress, emotional states, and environmental cues — can produce cravings for months or even years, but these become less frequent and less intense over time.
Understanding which component you are experiencing changes how you respond. Physical symptoms are time-limited and biological — they will end. Psychological triggers are learned associations — they can be unlearned.
Nicotine Replacement Therapy (NRT) addresses the physical component by providing controlled nicotine, eliminating the shock of sudden deprivation while you address the behavioural habit. Clinical trials show NRT approximately doubles quit success rates. Varenicline (Champix/Chantix) partially activates nicotinic receptors while blocking nicotine, reducing both cravings and reward from slipping. Bupropion reduces dopaminergic cravings through a different mechanism. All three significantly outperform willpower alone for high-dependence smokers.
Complete guide to nicotine withdrawal symptoms: timeline, what causes them, and evidence-based ways to manage each one. From cravings to brain fog.
science · 6 min readWhat happens in your brain during nicotine withdrawal, day by day. A neuroscience-based timeline of every symptom, when it peaks, and when it ends.
science · 5 min readNicotine withdrawal is a measurable neurochemical event. Here's exactly what happens in your brain when you quit smoking — and why each symptom has a specific biological cause.
Free nicotine clearance calculator. Enter your last cigarette and watch live countdowns to carbon monoxide clearing (WHO's 12h mark) and nicotine (72h).
Free craving countdown timer. Nicotine cravings peak and pass in 3–5 minutes; start the timer, follow the 4-7-8 breathing guide, and outlast this one.
Free lung recovery timeline. Enter your quit date to see what your lungs and heart are doing right now, from 20 minutes to 10 years, sourced to NHS and CDC.
Hour-by-hour guidance, craving tools, and a road that shows you exactly how far you have come.
Burnout is out on Android.
Every tool on this site stays free, needs no account, and runs entirely in your browser.
