Masculine dossier · first seen 1921
Guilherme
Stable Decline
Gradual decline from 2006
Peak era
2006
Peak births
39
Current vitality
Rare
Peak generation
Gen Z
Quick answers about Guilherme
How many people are named Guilherme?
An estimated 509 living Americans are named Guilherme.
How rare is Guilherme?
Guilherme is very rare among babies today, with 8 boys receiving the name in 2025, down 79.5% from its 2006 peak.
How old is the typical Guilherme?
The median age of a living American named Guilherme is approximately 19 years, with most bearers falling between 13 and 23 years old.
Is Guilherme still popular?
Not especially. Guilherme has been declining since its 2006 peak and registered 8 births in 2025.
Where is Guilherme most common?
Guilherme has its strongest geographic signal in Massachusetts, where it appears 24.6× more often than the national baseline.
1921Peak 20062025
Peak year
2006
Decline from peak
79.5%
2025
8
All-time
522
Where it lives now
Guilherme is most concentrated in Massachusetts — about 21.5× the national rate in the 2010s.
States where Guilherme is given more often than the national average — its present-day heartland.