https://sleepguru.me/Clear, sourced guides to healthy sleep and free calculators for bedtimes, wake-up times, naps, caffeine and jet lag. Every page is fact-checked against its sources.https://sleepguru.me/alcohol-sleep-calculator/https://sleepguru.me/alcohol-sleep-calculator/Thu, 29 Oct 2026 08:00:00 +0000Enter your bedtime and drinks to see the latest time for your last one, so most of the alcohol is processed before you sleep. Not a driving or sobriety tool.https://sleepguru.me/best-room-temperature-for-sleep/https://sleepguru.me/best-room-temperature-for-sleep/Thu, 29 Oct 2026 08:00:00 +0000For most adults, a bedroom of about 60 to 68°F (16 to 20°C) works best. Why a cool room helps, how humidity and bedding change it, and what to do on hot nights.https://sleepguru.me/best-time-to-take-a-nap/https://sleepguru.me/best-time-to-take-a-nap/Thu, 29 Oct 2026 08:00:00 +0000The best time to nap is early afternoon, in the natural post-lunch dip and at least 8 hours before bed. Why late naps backfire, and who should skip them.https://sleepguru.me/caffeine-calculator/https://sleepguru.me/caffeine-calculator/Thu, 29 Oct 2026 08:00:00 +0000Add your coffees, teas or energy drinks and your bedtime to estimate how much caffeine is still in your body when you lie down, and when it fades.https://sleepguru.me/caffeine-nap/https://sleepguru.me/caffeine-nap/Thu, 29 Oct 2026 08:00:00 +0000A caffeine nap means drinking coffee, then napping 15 to 20 minutes so the caffeine kicks in as you wake. What the studies found and when to skip it.https://sleepguru.me/can-a-night-owl-become-a-morning-person/https://sleepguru.me/can-a-night-owl-become-a-morning-person/Thu, 29 Oct 2026 08:00:00 +0000Partly. Genes set your starting point, but light and a fixed routine shifted night owls about two hours earlier in three weeks. What works and what slips back.https://sleepguru.me/can-you-catch-up-on-sleep/https://sleepguru.me/can-you-catch-up-on-sleep/Thu, 29 Oct 2026 08:00:00 +0000Partly. Extra sleep repays some sleep debt, but recovery takes days, not one lie-in, and weekends alone do not undo the effects of short weeknights.https://sleepguru.me/chronotype-calculator/https://sleepguru.me/chronotype-calculator/Thu, 29 Oct 2026 08:00:00 +0000Turn your real workday and free-day sleep times into a chronotype number (corrected mid-sleep) and your social jet lag, using the method sleep researchers use.https://sleepguru.me/circadian-rhythm-calculator/https://sleepguru.me/circadian-rhythm-calculator/Thu, 29 Oct 2026 08:00:00 +0000Estimate when your melatonin rises, when your body temperature bottoms out, and when light shifts your body clock earlier or later, from your free-day sleep.https://sleepguru.me/daylight-saving-time-sleep/https://sleepguru.me/daylight-saving-time-sleep/Thu, 29 Oct 2026 08:00:00 +0000Adjust to daylight saving time by shifting bedtime 15 to 20 minutes a night for a few nights before the change. Why spring is harder and how long it takes.https://sleepguru.me/does-alcohol-help-you-sleep/https://sleepguru.me/does-alcohol-help-you-sleep/Thu, 29 Oct 2026 08:00:00 +0000Alcohol helps you fall asleep faster, then breaks up the second half of the night and cuts REM sleep. Here is how a nightcap changes your sleep, drink by drink.https://sleepguru.me/does-blue-light-affect-sleep/https://sleepguru.me/does-blue-light-affect-sleep/Thu, 29 Oct 2026 08:00:00 +0000Yes, but brightness and timing matter more than color alone. What studies show about screens, night mode, warm bulbs and sleeping with the lights on.https://sleepguru.me/how-long-does-jet-lag-last/https://sleepguru.me/how-long-does-jet-lag-last/Thu, 29 Oct 2026 08:00:00 +0000Jet lag usually lasts about a day per time zone crossed, a little less flying west. See typical recovery times for US to UK, Europe, Japan and 12-hour trips.https://sleepguru.me/how-long-does-sleep-inertia-last/https://sleepguru.me/how-long-does-sleep-inertia-last/Thu, 29 Oct 2026 08:00:00 +0000Morning grogginess, or sleep inertia, is worst in the first 15 to 30 minutes and mostly clears within an hour. What makes it worse and what helps it fade.https://sleepguru.me/how-long-is-a-sleep-cycle/https://sleepguru.me/how-long-is-a-sleep-cycle/Thu, 29 Oct 2026 08:00:00 +0000A sleep cycle lasts about 90 minutes on average, but usually between 80 and 100. Here is what happens in each stage and why the first cycle is shorter.https://sleepguru.me/how-long-should-a-nap-be/https://sleepguru.me/how-long-should-a-nap-be/Thu, 29 Oct 2026 08:00:00 +0000For most adults, a nap of 10 to 20 minutes gives the quickest lift with the least grogginess. Here is what 5, 10, 20, 30, 60 and 90-minute naps each do.https://sleepguru.me/how-long-should-it-take-to-fall-asleep/https://sleepguru.me/how-long-should-it-take-to-fall-asleep/Thu, 29 Oct 2026 08:00:00 +0000Most healthy adults fall asleep in about 10 to 20 minutes. Here is what counts as normal sleep latency, when slow sleep onset is a concern, and what helps.https://sleepguru.me/how-many-sleep-cycles-do-you-need/https://sleepguru.me/how-many-sleep-cycles-do-you-need/Thu, 29 Oct 2026 08:00:00 +0000Most adults need about five sleep cycles a night, which is roughly 7.5 hours of sleep. See how many fit in 6, 7, 8 and 9 hours, and why total hours matter more.https://sleepguru.me/how-to-fix-sleep-schedule/https://sleepguru.me/how-to-fix-sleep-schedule/Thu, 29 Oct 2026 08:00:00 +0000Fix a sleep schedule by locking in a wake time, getting morning light, dimming evenings and moving bedtime 15 to 30 minutes a day. Skip the all-nighter.https://sleepguru.me/how-to-recover-from-an-all-nighter/https://sleepguru.me/how-to-recover-from-an-all-nighter/Thu, 29 Oct 2026 08:00:00 +0000Recover from an all-nighter with bright light, a short nap and early caffeine. Skip driving, then sleep a bit early tonight and keep your usual wake time.https://sleepguru.me/how-to-sleep-after-night-shift/https://sleepguru.me/how-to-sleep-after-night-shift/Thu, 29 Oct 2026 08:00:00 +0000Go to bed soon after you get home, keep morning light out of your eyes, and make the room dark, cool and quiet. A practical guide to daytime sleep after nights.https://sleepguru.me/how-to-switch-from-night-shift-to-day-shift/https://sleepguru.me/how-to-switch-from-night-shift-to-day-shift/Thu, 29 Oct 2026 08:00:00 +0000After your last night shift, take a short morning sleep, get afternoon daylight and go to bed at a normal hour. Here is how to switch back, days off included.https://sleepguru.me/is-6-hours-of-sleep-enough/https://sleepguru.me/is-6-hours-of-sleep-enough/Thu, 29 Oct 2026 08:00:00 +0000For most adults, 6 hours a night falls short and 5 is too little, while 7 meets the minimum. What two weeks of short nights does, and the rare exceptions.https://sleepguru.me/is-9-hours-of-sleep-too-much/https://sleepguru.me/is-9-hours-of-sleep-too-much/Thu, 29 Oct 2026 08:00:00 +0000Nine hours of sleep can be perfectly normal, especially if you are young, ill or catching up. When long sleep is just your need and when to see a doctor.https://sleepguru.me/is-it-bad-to-go-to-bed-at-2am/https://sleepguru.me/is-it-bad-to-go-to-bed-at-2am/Thu, 29 Oct 2026 08:00:00 +0000A 2 a.m. bedtime isn't harmful in itself if you still sleep 7+ hours at steady times. Trouble starts with early alarms, drifting schedules and missed daylight.https://sleepguru.me/is-it-better-to-sleep-2-hours-or-stay-up/https://sleepguru.me/is-it-better-to-sleep-2-hours-or-stay-up/Thu, 29 Oct 2026 08:00:00 +0000For most people, a short sleep beats none: even 90 minutes to 2 hours helps alertness and memory. How to pick 90 minutes vs 3 hours and time the alarm well.https://sleepguru.me/is-jet-lag-worse-east-or-west/https://sleepguru.me/is-jet-lag-worse-east-or-west/Thu, 29 Oct 2026 08:00:00 +0000Flying east is usually harder, because your body clock runs slightly longer than 24 hours and finds it easier to stay up late than go to bed early.https://sleepguru.me/jet-lag-calculator/https://sleepguru.me/jet-lag-calculator/Thu, 29 Oct 2026 08:00:00 +0000Enter the time difference and your usual sleep times for a day-by-day trip plan: when to seek light, when to avoid it, and how long adapting may take.https://sleepguru.me/morning-sunlight-how-long/https://sleepguru.me/morning-sunlight-how-long/Thu, 29 Oct 2026 08:00:00 +0000No study has set a dose, but 15 to 30 minutes outdoors soon after waking is a sensible practical start, with more on gray days. Here is what the research says.https://sleepguru.me/nap-calculator/https://sleepguru.me/nap-calculator/Thu, 29 Oct 2026 08:00:00 +0000Enter your wake-up time, bedtime and when you can lie down, pick a nap type, and get an alarm time that includes dozing off and leaves room for tonight's sleep.https://sleepguru.me/night-shift-sleep-calculator/https://sleepguru.me/night-shift-sleep-calculator/Thu, 29 Oct 2026 08:00:00 +0000Enter your night shift times and commute to get a daytime sleep window, an optional pre-work nap, a caffeine cut-off, and a plan for night one and days off.https://sleepguru.me/should-i-sleep-before-night-shift/https://sleepguru.me/should-i-sleep-before-night-shift/Thu, 29 Oct 2026 08:00:00 +0000Yes: a planned nap of 1.5 to 3 hours in the afternoon or early evening helps you stay alert overnight. Here is how to time it, even for your first night.https://sleepguru.me/should-you-get-out-of-bed-if-you-cant-sleep/https://sleepguru.me/should-you-get-out-of-bed-if-you-cant-sleep/Thu, 29 Oct 2026 08:00:00 +0000Yes: if sleep has not come after about 20 minutes, get up, do something calm in dim light and return when sleepy. Here is why it works and how to do it well.https://sleepguru.me/sleep-calculator/https://sleepguru.me/sleep-calculator/Thu, 29 Oct 2026 08:00:00 +0000Find a bedtime for your alarm, or a wake-up time for your bedtime, based on sleep cycles and the time you take to fall asleep. Free, with the method explained.https://sleepguru.me/sleep-debt-calculator/https://sleepguru.me/sleep-debt-calculator/Thu, 29 Oct 2026 08:00:00 +0000Add up the sleep you missed this week, see your net sleep debt in hours, and get a gentle catch-up plan with a bedtime that fits your usual wake-up time.https://sleepguru.me/sleep-deprivation-calculator/https://sleepguru.me/sleep-deprivation-calculator/Thu, 29 Oct 2026 08:00:00 +0000Count your hours awake and see how lab studies compare that much wakefulness with alcohol, plus crash odds after a short night. If you feel drowsy, don't drive.https://sleepguru.me/sleep-efficiency-calculator/https://sleepguru.me/sleep-efficiency-calculator/Thu, 29 Oct 2026 08:00:00 +0000Work out your sleep efficiency from one night or a week of sleep diary averages, see whether it is in the normal range, and learn how CBT-I uses the number.https://sleepguru.me/sleep-need-calculator/https://sleepguru.me/sleep-need-calculator/Thu, 29 Oct 2026 08:00:00 +0000Find the recommended hours of sleep for your age, a personal starting target based on how you sleep and feel now, and the bedtime that fits your alarm.https://sleepguru.me/sleep-schedule-calculator/https://sleepguru.me/sleep-schedule-calculator/Thu, 29 Oct 2026 08:00:00 +0000Enter your wake-up time now and the one you want. Get the number of days it takes and a daily table of wake-up, light, dim-light and bedtime targets.https://sleepguru.me/social-jet-lag/https://sleepguru.me/social-jet-lag/Thu, 29 Oct 2026 08:00:00 +0000Social jet lag is the gap between your sleep timing on workdays and free days. How it is measured, how common it is, what it is linked to and how to shrink it.https://sleepguru.me/when-to-stop-drinking-coffee-before-bed/https://sleepguru.me/when-to-stop-drinking-coffee-before-bed/Thu, 29 Oct 2026 08:00:00 +0000Research suggests finishing a regular coffee about 9 hours before bed, and strong caffeine drinks up to 13 hours before. Why even 6 hours may not be enough.https://sleepguru.me/why-do-i-fall-asleep-so-fast/https://sleepguru.me/why-do-i-fall-asleep-so-fast/Thu, 29 Oct 2026 08:00:00 +0000Dropping off within a few minutes is often a sign you are short on sleep, not a talent. Learn what counts as too fast, why it happens and when to see a doctor.https://sleepguru.me/why-do-i-feel-worse-after-a-nap/https://sleepguru.me/why-do-i-feel-worse-after-a-nap/Thu, 29 Oct 2026 08:00:00 +0000Feeling groggy or awful after a nap usually means you woke from deep sleep. Why it happens, why sleep debt makes it worse, and how to clear the fog faster.https://sleepguru.me/why-do-i-get-sleepy-in-the-afternoon/https://sleepguru.me/why-do-i-get-sleepy-in-the-afternoon/Thu, 29 Oct 2026 08:00:00 +0000The 2 p.m. slump comes mostly from your body clock and rising sleep pressure, not just lunch. Why it happens, why short nights make it worse, and what helps.https://sleepguru.me/why-do-i-sleep-better-on-the-couch/https://sleepguru.me/why-do-i-sleep-better-on-the-couch/Thu, 29 Oct 2026 08:00:00 +0000If you doze off easily on the sofa but lie awake in bed, your bed may have become a cue for being awake. Here is why that happens and how to retrain it.https://sleepguru.me/why-do-i-wake-up-at-3am-after-drinking/https://sleepguru.me/why-do-i-wake-up-at-3am-after-drinking/Thu, 29 Oct 2026 08:00:00 +0000Waking at 3 or 4 a.m. after drinking is a rebound: as alcohol wears off, sleep turns light, your heart races and your bladder fills. Here is what helps.https://sleepguru.me/why-do-i-wake-up-at-3am/https://sleepguru.me/why-do-i-wake-up-at-3am/Thu, 29 Oct 2026 08:00:00 +0000Brief waking in the night is normal; sleep gets lighter in the early hours. Here is why 3 or 4 a.m. is so common, what triggers it and how to drift off again.https://sleepguru.me/why-do-i-wake-up-before-my-alarm/https://sleepguru.me/why-do-i-wake-up-before-my-alarm/Thu, 29 Oct 2026 08:00:00 +0000Your body can learn when the alarm is due and start a stress-hormone rise about an hour before it. Why it happens, why you may still feel tired, and what to do.https://sleepguru.me/why-do-i-wake-up-tired/https://sleepguru.me/why-do-i-wake-up-tired/Thu, 29 Oct 2026 08:00:00 +0000Eight hours in bed is not always eight good hours of sleep. The usual reasons you wake up unrefreshed, from late coffee to a hot room, and when to see a doctor.https://sleepguru.me/why-does-coffee-make-me-sleepy/https://sleepguru.me/why-does-coffee-make-me-sleepy/Thu, 29 Oct 2026 08:00:00 +0000Coffee can leave you tired because caffeine only masks sleepiness, daily use blunts its effect, and short sleep wins out. Five reasons, and what helps.