Let me be honest: this article isn't sexy. There's no secret hack, no magic supplement, no expensive gadget. Just the fundamentals—the boring stuff that actually makes a difference.

When I was sleeping 4 hours a night during my startup years, I dismissed sleep hygiene as obvious advice for people who didn't have "real" sleep problems. Then I spent two years fixing my sleep, and guess what? The boring stuff turned out to be foundational.

These habits won't cure chronic insomnia by themselves—that usually requires CBT-I. But they create the conditions for good sleep. Skip them, and everything else becomes harder.

01 What Is Sleep Hygiene?

Sleep hygiene refers to the behaviors, environment, and habits that either support or sabotage your sleep. Think of it like dental hygiene: brushing your teeth won't fix a cavity, but neglecting it guarantees problems.

02 Your Sleep Environment

Your bedroom should be optimized for one thing: sleep. (Okay, two things.) This isn't about aesthetics—it's about creating conditions that align with your biology.

Temperature: The Most Underrated Factor

Your body temperature naturally drops 1-2°F to initiate sleep. If your room is too warm, your body struggles with this process. Research consistently shows the optimal bedroom temperature is 60-67°F (15-19°C)^[1].

If you're skeptical: try sleeping in a cooler room for one week. Most people notice a difference immediately. If 65°F feels cold, use warmer blankets—but keep the air cool.

Darkness: Your Body's Off Switch

Any light in your bedroom signals to your brain that it might be daytime. Even small amounts of light—a charging phone, an LED indicator, streetlights through curtains—can suppress melatonin production^[2].

Quiet (Or Consistent Noise)

Complete silence isn't always possible—or even necessary. What matters is avoiding unpredictable sounds that spike your alertness. A consistent background noise (white noise, fan, rain sounds) can actually improve sleep by masking disruptive sounds.

"It's not noise that wakes you—it's the change in noise. A sudden silence can be as disruptive as a sudden sound."

— Dr. Mathias Basner, University of Pennsylvania

Your Bed: For Sleep Only

This is stimulus control, one of the core principles of CBT-I. If you work in bed, scroll in bed, worry in bed, and watch TV in bed, your brain associates the bed with wakefulness. Reserve your bed for sleep (and sex). Everything else happens elsewhere.

03 Timing & Consistency

Your circadian rhythm—your internal 24-hour clock—thrives on consistency. Irregular sleep schedules confuse your body about when it should be alert and when it should sleep.

The Most Important Habit: Fixed Wake Time

If you take nothing else from this article: wake up at the same time every day, including weekends. Yes, even if you slept poorly. Yes, even if you were up late.

"But what if I only got 4 hours of sleep?" Wake up anyway. You'll be tired that day, but you'll build sleep pressure for a better night. Sleeping in to "catch up" perpetuates the cycle.

Bedtime Is Less Critical (But Still Matters)

Don't go to bed until you're actually sleepy—not just tired. If you go to bed because "it's bedtime" but you're not sleepy, you'll lie there awake, which trains your brain that bed is for lying awake.

That said, aim for a consistent bedtime window (within 30-60 minutes). Dramatic variation—2am one night, 10pm the next—confuses your circadian rhythm.

04 Substances That Sabotage Sleep

Caffeine: The Hidden Sleep Killer

Here's what surprised me: caffeine has a half-life of 5-6 hours. That means if you have 200mg of caffeine at 3pm (a medium coffee), you still have 100mg in your system at 9pm and 50mg at 3am^[3].

Caffeine doesn't stop you from sleeping—it reduces sleep quality. You might fall asleep fine but get less deep sleep. Studies show caffeine consumed 6 hours before bed still reduces total sleep by over an hour^[4].

The rule: No caffeine after noon. If you're sensitive, make it 10am or cut it entirely for a few weeks to see the difference.

Alcohol: The Sleep Quality Destroyer

"But alcohol helps me fall asleep!" True—it's a sedative. But it destroys sleep quality:

• Suppresses REM sleep (critical for emotional processing and memory)
• Causes fragmented sleep in the second half of the night as it metabolizes
• Relaxes throat muscles, worsening snoring and sleep apnea
• Creates dependence—you need it to fall asleep

Alcohol doesn't help you sleep; it sedates you. Sedation is not the same as sleep. If you drink, stop at least 3-4 hours before bed, and keep it moderate.

Nicotine: The Stimulant People Forget

Nicotine is a stimulant. It increases heart rate, raises blood pressure, and stimulates brain activity—the opposite of what you want before sleep. Smokers take longer to fall asleep, get less deep sleep, and wake more during the night.

05 Daytime Habits That Affect Sleep

Morning Light Exposure

Getting bright light exposure in the morning—ideally natural sunlight—sets your circadian rhythm. It tells your body "this is morning" and starts the countdown to melatonin release ~14-16 hours later.

Exercise: Timing Matters

Regular exercise improves sleep quality—that's well-established^[5]. But timing matters. Intense exercise raises your core temperature and stimulates your nervous system. Give your body time to cool down and calm down.

The guideline: Finish vigorous exercise at least 3 hours before bed. Light stretching or yoga before bed is fine—even beneficial.

Napping: Handle With Care

Naps aren't bad, but they reduce sleep pressure. If you're struggling to sleep at night, avoid naps entirely. If you must nap:

• Keep it under 20 minutes (avoid entering deep sleep)
• Nap before 3pm (later naps steal from nighttime sleep)
• Or do a full 90-minute cycle (but expect later bedtime)

06 Your Bedtime Routine

A consistent pre-sleep routine signals to your brain that sleep is approaching. It's not about specific activities—it's about consistency and calm.

The Buffer Zone (60-90 Minutes Before Bed)

When You Can't Sleep

If you've been lying awake for ~20 minutes (don't watch the clock—estimate), get up. Go to another room, do something boring in dim light, and return to bed only when sleepy. This prevents your brain from associating bed with frustrated wakefulness.

Written by

Kevin Li

Software Developer, Former Insomniac

Former 4-hours-a-night tech guy. Burned out at 31, spent two years fixing my sleep. Built this calculator because all the existing ones looked like they were made in 2005.