Melatonin Dosage Calculator

What Is Melatonin?

Melatonin is a hormone produced by the pineal gland that regulates the sleep-wake cycle (circadian rhythm). Over-the-counter melatonin supplements are widely used for insomnia, jet lag, shift work, and certain medical conditions. Doses vary by indication, age, and formulation. This calculator provides evidence-based dose ranges and timing for common uses. For broader sleep assessment, try the Epworth Sleepiness Scale Calculator and the Sleep Cycle Calculator.

Melatonin Doses by Indication

For trouble falling asleep, typical doses range from 0.3 to 5 mg taken about 1 hour before bedtime; 3 mg is a common starting dose. Jet lag (eastbound travel) often uses 0.5 to 5 mg before bedtime for 2 days before departure and 4 days after arrival. Westbound jet lag may require dosing for 4 days after arrival only. Insomnia in blind individuals uses a lower dose of 0.5 mg around 9 to 10 PM. Beta-blocker-associated insomnia may respond to 2.5 mg nightly for up to 4 weeks. Endometriosis trials have used 10 mg daily for up to 8 weeks under medical supervision.

Formulations and Safety

Melatonin comes as tablets, capsules, liquids, sprays, and dissolving strips. Lower doses (0.3 to 1 mg) may be as effective as higher doses for sleep onset with fewer next-day effects. Take melatonin 30 to 60 minutes before desired sleep. Side effects can include daytime drowsiness, headache, and vivid dreams. Melatonin is generally well tolerated short term but long-term safety data are limited. Consult a healthcare provider before use in children, during pregnancy, or with other medications.