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what temp is a fever

Most doctors consider a temperature of about 100.4°F (38°C) or higher a fever for both adults and children, depending on how it’s measured.

Quick Scoop: Key Numbers

  • Oral thermometer (in the mouth):
    Around 100–100.4°F (37.8–38°C) or higher is generally considered a fever.
  • Rectal, ear, or forehead (temporal) thermometer:
    100.4°F (38°C) or higher is usually counted as a fever.
  • Armpit thermometer:
    About 99°F (37.2°C) or higher is often considered a fever, though this method is a bit less accurate.

Normal body temperature is usually in the 97–99°F (36.1–37.2°C) range, and it can vary by time of day, age, and activity.

When to Worry (Adults)

You should get urgent medical help or call your local emergency number if an adult has:

  1. Temperature 103°F (39.4°C) or higher, or any fever plus:
    • Chest pain or trouble breathing.
 * Confusion, difficulty staying awake, or seizures.

 * Stiff neck and severe headache.
  1. Fever lasting more than 3 days, or getting worse instead of better.

When It’s a Child

For babies and young kids, the temperature and age both matter:

  • Babies under 3 months: Rectal temp of 100.4°F (38°C) or higher is an emergency; they should be seen right away.
  • Children 3–36 months: Fever of 102°F (38.9°C) or higher, or any fever that lasts more than a day or two, should be checked with a doctor, especially if they seem very unwell.

Quick Care Tips

  • Use a digital thermometer and follow the instructions for where you measure (mouth, rectum for babies if instructed, forehead, or armpit).
  • Focus on how the person looks and feels , not just the number: trouble breathing, confusion, rash, or severe pain are more concerning than a mild fever alone.
  • Keep hydrated, wear light clothing, and use fever-reducing medicine (like acetaminophen or ibuprofen) according to package or doctor instructions if needed.

If you tell me the age of the person, how you measured the temperature, and what symptoms they have, I can help you interpret it more specifically (not as a diagnosis, but with general guidance). Information gathered from public forums or data available on the internet and portrayed here.