Is My Baby’s Fever Normal? A Parent’s Guide to Baby Temperatures

Why Fevers Worry Parents

Few things spike parental anxiety faster than a warm forehead at 2 a.m. You grab the thermometer, see a number you don’t like, and the questions flood in: Is this normal? Should I call the doctor? Is my baby okay?

The truth: fevers are common in babies, and often they’re a sign the body is fighting something minor—like a cold or virus. But in certain cases, fever can mean something more serious. Knowing when to watch and when to act helps you feel calmer and more prepared.

What Counts as a Fever in Babies?

• Normal range: A baby’s typical temperature is around 97°F–100.3°F (36.1°C–37.9°C).

• Fever: 100.4°F (38°C) or higher (taken rectally, which is the most accurate method for babies).

• Low-grade temps (99–100°F): Often just normal variation, teething, or a warm environment—not necessarily illness.

When to Call the Pediatrician Immediately

• Under 3 months old: Any fever of 100.4°F (38°C) or higher requires a same-day call or ER visit. Babies this young are more vulnerable, and doctors take every fever seriously.

• 3–6 months old: Call if fever reaches 101°F (38.3°C) or higher, or if your baby seems unusually irritable, lethargic, or not feeding well.

• Over 6 months old: Call if fever hits 103°F (39.4°C) or higher, or if it lasts longer than 3 days.

Also call anytime your instincts say something feels “off.” You know your baby best.

Other Symptoms to Watch For

• Trouble breathing or very fast breathing

• Severe lethargy (baby is hard to wake)

• Persistent vomiting or refusal to feed

• Rash that doesn’t fade when pressed

• Signs of dehydration (dry mouth, no tears, fewer than 3 wet diapers in 24 hours)

If you see these alongside a fever, seek medical help right away.

What You Can Do at Home

• Keep baby comfortable: Dress them lightly, avoid heavy blankets.

• Offer fluids: Frequent breastfeeds, formula, or sips of water (if over 6 months).

• Monitor temperature: Check every few hours, not obsessively every 10 minutes.

• Use medication wisely: If recommended by your pediatrician, infant acetaminophen (and ibuprofen if over 6 months) can ease discomfort.

What Not to Do

• Don’t give aspirin (unsafe for babies).

• Don’t use cold baths or alcohol rubs—these can be harmful.

• Don’t panic at every number—focus on how your baby looks and acts.

Clinician’s Note

As both a pediatrician and a parent, I remind families: fever itself is not dangerous—it’s the body’s natural defense. What matters most is your baby’s age, symptoms, and overall behavior. A cheerful baby with a 101°F fever is often less concerning than a listless baby with a 100.4°F fever. Trust your gut, and never hesitate to call your doctor if you’re unsure.

Key Takeaways

• Fever = 100.4°F (38°C) or higher, rectally.

• Under 3 months: any fever is an emergency call.

• Over 6 months: most fevers are safe if baby is otherwise alert and drinking well.

• Watch for red-flag symptoms (trouble breathing, lethargy, dehydration).

• Comfort, fluids, and monitoring are your best tools.

Final word: Fevers can be scary, but most are signs of a healthy immune system at work. Stay calm, know the guidelines, and remember—you don’t have to figure it out alone.