What is a TLD? The complete domain-extension guide

The three categories

• **Generic TLDs (gTLDs)** — Open to anyone globally. Examples: .com, .net, .org, .info, .biz. Also includes the "new gTLDs" rolled out from 2014: .app, .dev, .blog, .shop, .agency, hundreds more.
• **Country-code TLDs (ccTLDs)** — Originally tied to a country or territory. Some are restricted to local residents (e.g., .ca requires Canadian presence), most allow global registration (.ai, .io, .me, .co, .tv). About 250 exist, one per ISO country code.
• **Sponsored TLDs (sTLDs)** — Run by a specific organization and gated. Examples: .edu (US accredited universities only), .gov (US government only), .museum, .aero, .post.

Top 20 TLDs by registered domains (2026)

How TLDs affect your site

For ranking purposes, Google treats every modern generic TLD equally. There is no SEO penalty for choosing .io over .com. The differences you feel are:

• **Trust and recall** — .com is what people type from memory. Other TLDs cost you 3-15% on direct-type traffic depending on audience familiarity.
• **Pricing** — Standard ranges from ~$10/yr (.com, .net) to ~$80/yr (.ai). Premium names can run into five and six figures.
• **Audience signal** — .ai signals AI startup; .dev/.io signal developer tool; .shop signals e-commerce; .org signals nonprofit (although technically open).
• **Geographic intent** — Some ccTLDs (.uk, .de, .fr) signal local presence to Google search, which can be a positive for local SEO and a negative for global brands.

Common questions

**"How do I pick a TLD?"** Default to .com. If your .com is taken and unaffordable, pick based on audience: .ai for AI products, .io or .dev for developer tools, .co or .net as broad fallbacks, and a niche TLD (.shop, .agency, .design) only if your industry strongly associates with it.

**"Are TLDs case-sensitive?"** No — example.com and EXAMPLE.com point to the same site. Domain names are always case-insensitive.

**"Can I have the same name on multiple TLDs?"** Yes, and it's common to do so for defensive brand protection. Most brands own at least .com plus 2-3 secondary TLDs.

Glossary of related terms

• **Domain name** — the full text address (example.com). Includes the SLD and TLD.
• **SLD (second-level domain)** — the part before the TLD ("example" in example.com).
• **Subdomain** — a prefix added to a domain (www.example.com, mail.example.com).
• **Registrar** — the company that sells the registration to you (Namecheap, Cloudflare, GoDaddy).
• **Registry** — the organization that operates the TLD (Verisign for .com, NIC.AI for .ai).
• **WHOIS** — the public database of domain registration data.
• **RDAP** — the modern HTTPS-based replacement for WHOIS.