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How do I take a temperature?

Children under 5

For advice about taking a temperature in a child under 5, see how to take a baby's or young child's temperature.

Using a digital thermometer

One way to check your temperature is to use a digital thermometer. You can buy these from supermarkets and pharmacies.

To use a digital thermometer:

  1. Clean the tip with cold water and soap, then rinse it.
  2. Turn the thermometer on.
  3. Put the tip under your tongue, towards the back of your mouth.
  4. Close your lips around the thermometer.
  5. Wait until it beeps or flashes.
  6. Check the temperature on the display.

You can also use a digital thermometer in your armpit. Make sure you keep your arm tight against your body until the thermometer beeps or flashes.

Digital ear thermometers

If you use a digital ear thermometer, follow the instructions that come with it.

You usually need to gently pull your ear up and back before putting the thermometer in your ear. This helps you get a more accurate temperature.

Important: Other thermometers

Do not use a glass thermometer or a forehead strip.

Glass thermometers can be dangerous and forehead strips are not accurate.

If you do not have a thermometer

You can often still tell if you have a high temperature even if you do not have a thermometer.

Touch your chest and back. If they feel hotter than usual, you may have a high temperature. You may also have other symptoms such as feeling shivery (chills).

Touching your forehead is not a very accurate way of checking your temperature.

What is a high temperature?

Normal body temperature is different for everyone and changes during the day.

A temperature of 38C or more is usually considered a high temperature (fever).


It's not always easy to take a temperature accurately.

If you feel hot or shivery, you may have a high temperature even if a thermometer says your temperature is below 38C.

What should I do if I have a high temperature?

Try to stay at home and avoid contact with other people if you have a high temperature or do not feel well enough to do your normal activities.

Use the NHS 111 online service to find out what to do.


Only call 111 if you cannot get help online.

Page last reviewed: 31 March 2020
Next review due: 31 March 2023