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GlossaryExtensions

Domain extension

A domain extension is the part of a domain name after the last dot, such as .com, .ai or .xyz; technically it is the top-level domain, or TLD, and each one is run by a registry under its own rules and prices.

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Also called extension · domain suffix

Domain extension, explained

Extensions fall into groups. Legacy generic TLDs such as .com, .net and .org predate ICANN's 2012 expansion round, which added more than 1,200 new gTLDs such as .xyz, .app and .shop. Country-code TLDs such as .de, .uk, .co, .io and .ai belong to countries and territories, and several are marketed worldwide as generic. Some registries also sell second-level names such as .co.uk, which buyers treat as an extension even though the TLD is .uk.

The registry sets the terms that matter to a holder: registration and renewal prices, premium tiers, who may register, since some ccTLDs require a local presence, minimum terms and the dispute policy. Read them before you buy, because a cheap first year can hide an expensive renewal, and a country-code registry can change its rules.

Liquidity is uneven. At the end of Q2 2026 there were 401.6 million registrations across all TLDs, of which .com held 166.6 million, ccTLDs 148.6 million and new gTLDs 52.9 million. Resale demand is more concentrated still: .com made up 66% of Sedo's sales in 2025. A name in a thin market may find no buyer at any sensible price, so value names extension by extension instead of assuming a good word is good everywhere.

The .ai extension shows how meaning can create demand. Anguilla's country code passed one million registered names in January 2026, and .ai deals on Escrow.com crossed $10 million in a quarter for the first time in Q4 2025. More choice is coming: ICANN's 2026 application window drew more than 1,600 applications, and 1,616 will proceed.

Example. The same word can be a liquid asset in .com and close to unsellable in a small new extension, so investors value each extension separately.

Go deeper How to Value and Price a Domain Name

Sources

  1. ICANN — ICANN opens application window for new generic top-level domains (Apr 30, 2026)
  2. DNIB.com (Verisign) — The Domain Name Industry Brief, Q2 2026 (July 23, 2026)
  3. InterNetX and Sedo — Global Domain Report 2026 (data for 2025)
  4. Domain Name Wire — New report contains interesting aftermarket domain name data (Mar 23, 2026)
  5. Domain Name Wire — .ai namespace hits 1 million domain names (Jan 28, 2026)
  6. Escrow.com — Domain Investment Index Q4 2025 (published Mar 4, 2026)
  7. ICANN — 2026 round closes with more than 1,600 new gTLD applications (Aug 13, 2026)
  8. CircleID — ICANN confirms 1,616 applications will proceed in 2026 new gTLD round (Sept 23, 2026)

Education, not financial, legal or tax advice. Domain investing is speculative and most domain names never sell. Read the disclaimer.

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