How to take your temperature accurately

With a fever being one of the first symptoms of Coronavirus, here's how to take your temperature correctly

How to take your temperature accurately
(Image credit: Getty)

Never worried about how to take your temperature before? Coronavirus has changed all that. A fever is one of the first symptoms of the virus, along with a dry cough, so knowing how to take your own temperature and the temperature of your loved ones accurately has never been more important. Read on for advice on taking your temperature correctly, whatever kind of thermometer you have.

If you don't own a thermometer yet, then check out our guide to the best thermometers available online right now.

Firstly, what counts as a fever?

First things first, you need to know what a normal temperature is. For children, a normal temperature is around 36.4°C and in adults in it's around 37°C. Anything over 38°C in adults or children is classed as a fever.

You need to contact 111 or your GP immediately if a child under three months has a temperature of 38°C or higher, or a child aged three to six months has a temperature of 39°C or higher.

Why do we get a fever?

It's important to remember that a fever is your body's natural response to fighting an infection. By increasing your body’s temperature, a fever stimulates your immune system and makes it harder for the bacteria and viruses that cause infections to survive.

How to take an adult's temperature

A digital thermometer is the best way to take your temperature. Thermometers comes in all shapes and sizes, so always check the operating instructions before using yours. 

As a general rule: digital thermometers with a probe are used to record temperatures from the mouth or armpit, while digital thermometers with a changeable head sensor are used on the forehead or ear.

  • Digital thermometers with a probe are used to record temperatures from the mouth or armpit
  • Digital thermometers with a changeable head sensor are used on the forehead or ear
  • Some digital thermometers are designed for use in the ear only, but the NHS warns the reading may not be accurate if the thermometer is not correctly placed in the ear

How to take your temperature in your mouth

  • Reset the thermometer
  • Clean it by wiping with antiseptic or washing with water and washing up liquid
  • Place the thermometer under the tongue and close your month
  • Leave in place until you hear the beep, which usually takes a minute or less
  • Read the level shown on the digital display

How to take your forehead temperature

  • Reset the thermometer
  • Place the digital thermometer sensor head in the middle of the forehead
  • Slowly slide the thermometer towards the top of the ear, always keeping in contact with the skin
  • Stop when you reach the hairline and read the temperature
  • NB. Some forehead thermometers don't need to be slid across the skin so check yours

How to take your temperature in your ear

  • Add a clean probe tip (if needed) and reset the thermometer
  • Gently tug on the ear, pulling it up and back to help straighten the ear canal
  • Gently insert the thermometer until the ear canal is fully sealed off, then squeeze and hold the button for one second
  • Remove the thermometer from the ear and read the temperature

How to take a baby or young child's temperature

Take a baby or child under 5's temperature under their armpit

(Image credit: Getty)

For babies and children under five, the NHS recommends you use a digital thermometer and take their temperature under their armpit for the most accurate reading.

Simply place the thermometer under their armpit and hold their arm firmly but gently against their side for the length of time your thermometer's instructions specify, which is normally about 15 seconds. Most digital thermometers will beep when they're ready to be read.

How to take your temperature without a thermometer

If you haven't got a thermometer but want to check whether somebody has a fever, here are the signs to look out for:

  • Skin feels hot to the touch. Feet and hands may feel cooler
  • Skin is flushed on the face and cheeks
  • The person is shivering or going hot and cold
  • Feeling tired or weak
  • Loss of apetite