Baby Temperature Guide

Is it a fever? Normal baby temperature by method. Free, private and instant.

How to use the Baby Temperature

  1. Pick metric (cm, kg) or imperial (ft, in, lb) units.
  2. Enter temperature reading.
  3. Choose how was it taken?: Rectal (bottom), Ear, Forehead (temporal), Mouth (older child) and more.
  4. Choose child’s age: Under 3 months, 3 to 36 months or Over 3 years.
  5. Press Calculate to get an instant result with a colour scale, chart and plain-English explanation.

About the Baby Temperature

A normal body temperature is about 36.5 to 37.5°C (97.7 to 99.5°F), but the reading depends on how it is taken. Enter your baby’s reading, the method and age to see whether it is normal, a fever or needs urgent care, with an easy chart.

Also known as: baby fever chart, normal baby temperature, infant fever calculator, when is a baby's fever too high.

Worked example

Estimated body temperature: 37.2 °C (Normal). A rectal reading of 37.2°C (99.0°F) equals about 37.2°C core temperature: normal. This temperature is in the normal range.

Formula and cut-offs

Fever = core temperature of 38.0°C (100.4°F) or higher. Approximate adjustment to a rectal-equivalent reading: ear +0.2, forehead +0.2, mouth +0.4, armpit +0.7 °C. Under 3 months, any fever needs urgent medical care.

Frequently asked questions

What temperature is a fever in a baby?

38°C (100.4°F) or higher taken rectally, or the equivalent for other methods.

What should I do if a newborn has a fever?

A fever in a baby under 3 months is an emergency. Go to a doctor or hospital immediately.

Is an armpit reading accurate?

It reads lower than the core temperature. A raised armpit temperature should be confirmed with a rectal or ear reading.

Sources and references

Written and checked by the MediHub editorial team against the sources above. Read how we build and review our calculators.

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Last updated . This calculator is for education only and is not medical advice. See the medical disclaimer.