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The Sleep Math Blog

Research breakdowns, calculator deep-dives, and sleep science updates.

Rumpled bed sheets in dim early-morning light with a clock on the bedside table
Sleep Science May 20, 2026

Sleep Debt Is Real — Here's the Math

You can survive on 6 hours a night. For a while. Then the bill arrives — and a landmark study proved you will not even notice it happening.

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Half-finished cup of coffee on a bedside table in late afternoon light
Sleep Science May 19, 2026

Caffeine Half-Life: What Drake et al. Actually Found

That afternoon coffee you swore was "early enough"? A landmark study proved it still costs you an hour of sleep — and you will not even feel it happening.

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Bedside alarm clock at dawn next to an open notebook
Sleep Science May 15, 2026

Why the '8 Hours' Rule Is Wrong

Eight hours isn't a prescription — it's an average. The real number is written into your genes, age, and chronotype. Here is how to find it.

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Bedroom with warm lamp lighting at night
Sleep Hygiene May 14, 2026

5 Bedtime Habits That Are Ruining Your Sleep

Struggling to fall asleep or waking up exhausted? These 5 common nighttime habits could be the reason — and the science-backed fixes are simpler than you think.

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Coming next

  • The Science Behind Your Chronotype
  • Why You Wake Up Tired (Even After 8 Hours)
  • Blue Light and Melatonin: What the Research Actually Shows
  • Alcohol and Sleep: What One Drink Actually Does

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