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Melatonin Dosage Calculator

Created by Łucja Zaborowska, MD, PhD candidate
Reviewed by Steven Wooding
Based on research by
Schwertner A, Conceição Dos Santos CC, Costa GD, Deitos A, de Souza A, de Souza IC, Torres IL, da Cunha Filho JS, Caumo W. Efficacy of melatonin in the treatment of endometriosis: a phase II, randomized, double-blind, placebo-controlled trial.; Pain; June 2013See 1 more source
Herxheimer A, Petrie KJ Melatonin for the prevention and treatment of jet lag; Cochrane Library; April 2002
Last updated: Jan 18, 2024

Melatonin dosage calculator tells you a specific melatonin dose needed for a given indication (condition). This tool will also compute the number of tablets, strips, spray applications, or the liquid volume required for a chosen therapy period. 🛏️

Would you like to know:

  • How to take melatonin?
  • How many mg of melatonin should I take?
  • How much melatonin is too much?, or
  • How long does melatonin take to work?

If the answer is yes, follow the article below! You may also read about melatonin side effects and dosage of melatonin for kids.

What is melatonin?

Melatonin is a natural hormone produced by the pineal gland - a small organ located near the center of the brain. Melatonin regulates the sleep-wake cycle of the human brain.

Melatonin is produced artificially to cure disorders caused by the melatonin insufficiency or its improper secretion.

Reasons to take melatonin include:

  • Troubles with falling asleep;
  • Shift-work;
  • Jet lag;
  • Sleep disorders in blind people;
  • Endometriosis; and
  • Insomnia caused by beta-blockers (hypertension drugs).

Average dose of melatonin for adults ranges between 0.5-10 mg. The harmful effects of melatonin begin to dominate at around 30 mg - however, this maximum dosage threshold might differ in individual cases.

Melatonin side effects 📍

Melatonin shouldn't cause any side effects when used properly; however, it is essential to know the max dose of melatonin and lookout for all the alarming symptoms listed below.

  • Signs of allergic reaction: swelling of your body parts (especially face), hives, trouble breathing - call for help immediately!
  • Drowsiness;
  • Increased sweating;
  • Weird dreams;
  • Feeling irritable, depressed mood, mood shifting;
  • Stomach pain, headache; and
  • Dizziness.

Would you like to know how much sleep you should get every day? Try the sleep cycle calculator. 😴

How much melatonin should I take?

In this paragraph, we'll tell you the typical melatonin dosage for adults for all the enumerated indications. You may also use our melatonin dosage charts to find your perfect way of administration.

💡 Remember: melatonin dosage by weight is not a proper way to dose the drug. Melatonin requires fixed amounts of medication for all the different indications.

💡 When you ask yourself "how much melatonin should i take" always consider the lowest dose possible, and proceed to the larger amount only if the smaller one fails to work.

  1. Trouble falling asleep

    Dosage: 0.3-5 mg daily, taken 1 hour before sleep.

  2. Jetlag ✈️

    Dosage: 0.5-5 mg:

    • Eastbound travel (US→Europe): Take melatonin for two days before the flight, around 7 PM. Continue taking melatonin for 4 days after arrival, right before going to bed.
    • Westbound travel (Europe→US): Take melatonin for 4 days after arrival, right before going to bed.
  3. Sleep cycle disorders in blind people

    Dosage: 0.5 mg, taken around 9-10 PM, before going to sleep.

  4. Beta-blockers insomnia
    Dosage: 2.5 mg daily, for up to 4 weeks.

  5. Endometriosis

    Dosage: 10 mg daily, for up to 8 weeks.

Everything's done? Try out the variety of our dosage tools:

Melatonin for kids

When we ask ourselves "How many mg of melatonin for an adult do we need?", we shouldn't forget that children can possibly take melatonin too. Of course, such an application requires strict indications and medical consultation.

Generally, it is not recommended for healthy children to take melatonin on a daily basis.

Always follow your doctor's advise and recommendations.

  • Dosage: Children should start their dosage at the lowest possible amount, that is 0.5-1 mg, taken 30-60 min before sleep.
  • Always take care of your child's good sleep hygiene - limit screen device use and set the fixed time of going to sleep.


How do I calculate the correct dosage of melatonin?

To estimate how many mg of melatonin you should take as an adult:

  1. Check the correct indication for your melatonin intake.
  2. There is no specific melatonin dosage by weight. You don't need to consider that.
  3. To double-check, you can use our melatonin dosage calculator.
  4. Do not exceed the recommended max dose of melatonin.
  5. Do not prolong the duration of treatment.
  6. If you feel that melatonin is helping you and want to take it longer, consult your physician first.

How many melatonin gummies can I take?

To estimate the proper dose of melatonin gummies:

  1. Check the dose in one gummy on your melatonin package.
  2. See the recommended doses for your indication (disease).
  3. Now, divide the dose by the amount of melatonin in one gummy.
  4. Let's reckon you should take melatonin for endometriosis. The recommended dose is 10 mg a day. You've got gummies that contain 5 mg of melatonin each.
  5. To count the number of gummies (N):
    N = 10 mg/5 mg
    N = 2
  6. In this case, you need to take two gummies per day.

How much melatonin should I take if I weigh 197 lb?

The is no specific melatonin dosage by weight. The dose depends on the indication for melatonin use and your reaction to the drug (some people might need higher doses, but that is in no way affected by the individual's weight).

How many mg of melatonin should I take for beta blockers insomnia?

The recommended melatonin dose for beta blockers insomnia is 2.5 mg a day. The maximum duration of treatment should not exceed four weeks.

Łucja Zaborowska, MD, PhD candidate
Trouble falling asleep
Medication type
Tablets/ capsules
Therapy duration
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