Rex is a moderately popular boys' name in England & Wales, ranking #216 in 2024 with 228 recorded births. The name reached its all-time peak in 2021 with 396 births ranking #142. Since 1996, the popularity has increased by 2,750.0%. In 2024, approximately 1 in every 1,218 boys born was named Rex. FALLING Recent data shows the name is currently falling.