A TLD, short for top-level domain, is the last part of a domain name, after the final dot, such as .com, .org or .ai. It is also called a domain extension. Every domain sits under one TLD, which is run by a registry that sets its rules and wholesale price.
Types of TLDs
Generic TLDs are open to anyone, such as .com, .net and .org, along with hundreds of newer ones like .app, .shop and .xyz that were added from 2013 onward. Country-code TLDs are two letters long and belong to a country or territory, such as .ca for Canada or .uk for the United Kingdom. Some country codes, like .io, .ai and .co, are widely used by startups around the world because of what they look like they stand for.
Why the TLD Matters for Value
The extension has a large effect on what a domain is worth. A .com is the default most people type and trust, so the same name is usually worth far more as a .com than under any other extension. Some extensions, like .ai for artificial intelligence companies, have strong demand of their own. Most newer extensions have a thin resale market, so names under them sell for much less.
TLD vs Second-Level Domain
In a name like example.com, com is the TLD and example is the second-level domain, the part you choose when you register. Some country codes add another level, such as .co.uk, where the name you register sits under co.uk. Only real TLDs work, so a typo like .con is not a valid extension at all.
The Domibot appraisal adjusts every value for the extension, and the availability checker shows whether a name is free across .com and 11 other popular TLDs.