.dev vs .io

.io is twice the size of .dev: about 1.37 million domains in October 2026 against 712,600 in June 2026. .dev grew 43% in a year; .io grew 20% since September 2025, by independent estimates.

.dev is a generic TLD, run by Google Registry, open to the public since February 2019. .io is the country code of the British Indian Ocean Territory, run by Internet Computer Bureau.