You can perform a WHOIS lookup using various online tools. WHOIS provides information about the domain, including its creation date, expiration date, and the registrar. Websites like WHOIS.net or ICANN WHOIS Lookup can help with this.
Domain Registrar's Website:
If you know the domain registrar where the domain is registered, you can log in to your account on their website. Most registrars provide details about the domain, including its creation date.
Wayback Machine (Internet Archive):
The Wayback Machine allows you to view archived versions of websites. While it doesn't directly provide domain age, you can see when the website was first archived, giving you an approximate idea of the domain's age.
Domain Age Checker Tools:
There are online tools specifically designed to check domain age. These tools typically use WHOIS data and other sources to provide an estimate of when a domain was created. Examples include Domain Age Checker and Small SEO Tools.