Body Temperature by Method
A “normal” temperature depends on where it is measured. This chart compares normal ranges and fever thresholds for oral, rectal, ear, armpit and forehead readings.
Normal ranges and fever thresholds
| Method | Typical normal range | Fever at or above | Compared with oral |
|---|---|---|---|
| Oral (mouth) | 97.6–99.6 °F (36–38 °C) | 100 °F (38 °C) | — |
| Rectal | 98.6–100.4 °F (37–38 °C) | 100.4 °F (38 °C) | 0.5–1 °F higher |
| Ear (tympanic) | 98.6–100.4 °F (37–38 °C) | 100.4 °F (38 °C) | 0.5–1 °F higher |
| Forehead (temporal) | 97.1–99.1 °F (36–37 °C) | 100.4 °F (38 °C) | Often 0.5–1 °F lower |
| Armpit (axillary) | 96.6–98.6 °F (36–37 °C) | 99 °F (37 °C) | 0.5–1 °F lower |
Notes
Rectal readings are closest to core body temperature and are recommended for babies and young children. Oral readings are reliable for older children and adults if they have not eaten or drunk anything hot or cold for 15 minutes. Armpit readings are convenient but least accurate. Normal ranges vary from person to person and through the day. This chart is general information, not medical advice — use the body temperature converter to check a reading.
Frequently asked questions
Is armpit temperature lower than oral?
Yes, usually by about 0.5–1 °F (0.3–0.6 °C).
Which method is most accurate?
Rectal, especially for infants.
Is 99 °F under the arm a fever?
It is at the usual armpit fever threshold of 99 °F (37.2 °C).
Do forehead thermometers read lower?
Often slightly — follow the device’s instructions and compare with another method if unsure.