How to Take Your Temperature
Taking your body temperature is a simple yet important way to monitor your health. It helps detect fever, track illness, and guide decisions about when to rest, seek treatment, or call a doctor. You can measure temperature using different methods—oral, ear, rectal, armpit, or forehead—and each one has its own best use.
Today, most people rely on digital thermometers. These are safer and easier to use than the older glass thermometers that contain mercury. Digital thermometers provide fast, accurate readings and are widely available at pharmacies.
Types of Thermometers and How They Work
Understanding the different types of thermometers helps you choose the best one for your needs.
- Oral Thermometer: Measures heat under the tongue. It’s one of the most common types for older children and adults.
- Rectal Thermometer: Used for infants and young children because it provides the most accurate reading. It is inserted gently into the rectum.
- Tympanic (Ear) Thermometer: Uses infrared sensors to detect heat from the eardrum. Quick and non-invasive, but not ideal if the person has an ear infection or excess wax.
- Temporal (Forehead) Thermometer: Scans the forehead’s surface to measure temperature. Easy and gentle, often used for babies and toddlers.
- Axillary (Armpit) Thermometer: Measures body heat from the underarm. It’s less accurate but useful for quick checks when other methods aren’t possible.
How to Prepare for an Accurate Reading
No matter which method you choose, preparation helps ensure accuracy. Here are tips to get a reliable temperature reading:
- Wash your hands before and after handling the thermometer.
- Clean the thermometer with rubbing alcohol or warm soapy water before and after each use.
- Sit or lie down calmly for a few minutes before checking your temperature.
- If you’re taking an oral temperature, wait at least 30 minutes after eating or drinking anything hot or cold.
- Use a separate, labeled thermometer for rectal and oral use to avoid cross-contamination.
Step-by-Step Instructions for Each Method
Oral Method
- Place the thermometer tip under the tongue.
- Close your lips and breathe through your nose.
- Wait for the beep or signal from the thermometer.
- Remove and read the display.
Best for: Adults and children over age 4.
Rectal Method
- Apply a small amount of lubricant like petroleum jelly on the tip.
- Lay the infant on their back with knees bent or on their stomach.
- Insert the tip about 1/2 inch to 1 inch into the rectum.
- Hold still and wait for the reading.
Best for: Infants and toddlers under 3 years old.
Ear Method
- Pull the ear back and up (for children over 1) or back and down (for infants).
- Insert the thermometer gently into the ear canal.
- Press the button and wait for the beep.
Best for: Children over 6 months and adults.
Forehead Method
- Place the thermometer flat on the center of the forehead.
- Press the scan button and move it across to the temple or follow the device’s instructions.
- Release and read the result.
Best for: Quick checks on all ages, especially babies.
Armpit Method
- Place the tip of the thermometer in the dry center of the armpit.
- Hold the arm down firmly against the body.
- Wait for the beep or indicator.
Best for: A backup method when others aren’t available.
What Is a Normal Temperature?
Normal body temperature can vary depending on the method used and the person’s age. General guidelines include:
| Method | Normal Range |
|---|---|
| Oral | 97.6–99.6°F (36.5–37.5°C) |
| Rectal | 98.6–100.4°F (37.0–38.0°C) |
| Ear/Forehead | 97.6–99.5°F (36.5–37.5°C) |
| Armpit | 96.6–98.6°F (35.9–37.0°C) |
A temperature of 100.4°F (38°C) or higher is considered a fever for most people.
When to Seek Medical Advice
Taking your temperature is just one piece of information. Seek medical advice if:
- You have a fever for more than 3 days.
- A child under 3 months has a temperature over 100.4°F (38°C).
- Fever is paired with symptoms like rash, stiff neck, vomiting, confusion, or difficulty breathing.
- You feel weak, dehydrated, or faint.
- A fever doesn’t respond to over-the-counter medicines.
Tips for Monitoring and Recording
- Keep a log of temperature readings during illness.
- Write down the time, method, and result.
- Share this record with your doctor if symptoms persist or worsen.
