Normal body temperature is different for everyone and changes during the day.
A high temperature is usually considered to be 38C or above. This is sometimes called a fever.
You may have a high temperature if:
If you feel hot or shivery, you may have a high temperature even if a thermometer says your temperature is below 38C.
You do not need to take your temperature using a thermometer, but you can if you have one.
Make sure you use it correctly to help get an accurate result. See how to take a temperature.
There are some things you can do to help treat a high temperature.
get lots of rest
drink plenty of fluids (water is best) to avoid dehydration – drink enough so your pee is light yellow and clear
take paracetamol or ibuprofen if you feel uncomfortable
Try to stay at home and avoid contact with other people until you do not have a high temperature.
You can call 111 or get help from 111 online.
Many things can cause a high temperature. It's not usually a sign of anything serious.
It's often just caused by your body fighting an infection, such as a cold or flu.
Sometimes it could be a sign of something more serious if your temperature is very high or will not come down.
This page is for adults. For advice about children, see high temperature (fever) in children.