Editorial Standards

Sources we use

Every article lists its sources at the end. We rely on:

• Guidance from sleep medicine bodies, such as the American Academy of Sleep Medicine and the National Sleep Foundation.
• Government health agencies, such as the U.S. Food and Drug Administration.
• Peer-reviewed research, linked through PubMed or the journal. We check that each study exists and that it says what we say it says.

We don't cite blogs, forums or product pages as evidence. When the research is mixed or thin, we say so, using words like "may" or "tends to" rather than stating it as fact.

How the calculators work

Each calculator uses a simple, published method and explains it on its page:

• Sleep and nap calculators: 90-minute sleep cycles plus an adjustable time to fall asleep.
• Caffeine calculator: an adjustable caffeine half-life (5 hours by default).
• Sleep by age: the recommended ranges from the American Academy of Sleep Medicine and the National Sleep Foundation.

The numbers and charts in our articles are calculated with the same formulas, so they match the tools. These are averages; your own sleep may differ, and we say that wherever it matters.

Keeping articles current

Each article shows the date it was last updated. When guidance changes or we find a better source, we revise the article and update the date.

Health information, not medical advice

Our articles explain general sleep science. They are not a substitute for a doctor. Wherever a symptom could signal a medical problem, such as loud snoring with pauses in breathing, or insomnia lasting weeks, we say to see a doctor. Read our full medical disclaimer.

Advertising stays separate

SleepTimeCalc is supported by our partner, Titan Recovery. Partner content is always labelled Sponsored or From our partner, and it sits outside the article text. Articles never recommend a product in the body, and partnerships never change a calculator's result. We don't show ads or partner content on articles about children or teens.