What is a really high fever?

Generally, a fever above 103°F (39.4°C) is considered a really high fever and should be addressed promptly. For infants under 3 months, any temperature above 100.4°F (38°C) is serious.

For adults, a fever consistently over 103°F (39.4°C) is definitely really high and needs immediate medical attention. For babies under 3 months, any fever over 100.4°F (38°C) is an emergency. Don't delay seeing a doctor.

I totally get why you'd ask, it's always worrying when someone has a fever. For adults, generally anything above 103°F (39.4°C) is considered quite high and a reason to seek medical advice. For children, especially infants, even lower temperatures can be a concern. It's always best to consult a doctor.

A fever generally considered very high for adults is above 103°F (39.4°C).

When my kid had 102.5°F, I was already panicking! So, 103°F is really high, wow. Does anyone else get super anxious when the fever crosses 102°F? It just feels so scary, no?

For an adult, a fever above 103°F (39.4°C) is definitely a really high fever. But for infants and small children, even a lower temperature can be serious. Anytime there's a high fever, especially with other worrying symptoms, you absolutely must get it checked by a doctor for safety. Don't take chances.