My daughter head circumference was 33 centimeters at 3 weeks now its 36 centimeters at 1 month is that normal?

Many variables: Heads/Brains grow rapidly at this age but growth isn't the only variable when considering head circumference. The measurements could vary if it wasn't taken exactly the same way. When you follow up for the 2 month visit, your Pediatrician will plot another measurement on a growth curve and compare it to prior records. As long as your baby is feeding/acting/developing normally, I wouldn't worry.

Not unusual: Newborn head circumference frequently changes, sometimes dramatically, in first 1-2 months as the head regains normal shape after birth. During birth ,head frequently misshapen to allow delivery. Head circumference can then change a lot. Also depends on skill and accuracy of person taking the measurement. Pop in to doc's office for weekly check of size over next month, and have same person measure

Repeat Head Measure: Your daughter's head circumference at 3 weeks old was recorded at 33 cm. At age one month (one week later) was recorded at 36 cm. The normal rate of head growth is about 2 cm per month during the first 3 months. Your baby should return to the doctor soon to re-measure and to examine for other findings that may indicate rapid head growth. It is possible the initial measurement was in error.