ccTLD (Country Code Top-Level Domain)

What is a ccTLD?

A ccTLD (Country Code Top-Level Domain) is a two-letter top-level domain reserved for a specific country, sovereign state, or dependent territory. These codes are based on the ISO 3166-1 alpha-2 standard, the same codes used for country abbreviations in international contexts.

How ccTLDs Are Assigned

IANA (Internet Assigned Numbers Authority) delegates ccTLDs to designated managers in each country. These managers, often called NIC (Network Information Center) operators, set their own policies for:

• Who can register domains
• Registration requirements and verification
• Pricing structures
• DNS and RDAP/WHOIS services

This decentralized management means ccTLD policies vary significantly between countries.

Common ccTLD Categories

Unrestricted ccTLDs

Many ccTLDs are open to global registration without residency requirements:

Restricted ccTLDs

Some ccTLDs require local presence or citizenship:

Heavily Restricted ccTLDs

A few ccTLDs have strict limitations:

• .gov.uk: UK government only
• .edu.au: Australian educational institutions
• .mil: US military

Popular ccTLDs for Tech Companies

Several ccTLDs have transcended their geographic origins:

.io (British Indian Ocean Territory)

Despite representing a small territory, .io has become the unofficial TLD for tech startups. The "io" resonates with "input/output" in computing, making it feel natural for APIs, developer tools, and SaaS products.

.ai (Anguilla)

The artificial intelligence boom has made .ai one of the most valuable ccTLDs. Companies like x.ai and stability.ai have legitimized it for AI ventures.

.co (Colombia)

Marketed as an alternative to .com, .co has gained adoption for its similarity to "company" and "commercial." Twitter (t.co), Google (g.co), and Amazon (a.co) use .co for URL shortening.

.me (Montenegro)

Perfect for personal brands and portfolios, .me creates memorable domains like "hire.me" or "about.me."

Technical Considerations for ccTLDs

RDAP/WHOIS Support

Not all ccTLDs have implemented RDAP. When building domain tools, you may need fallback to WHOIS or handle unsupported TLDs gracefully.

// Check coverage before querying
const coverage = await fetch('https://domscan.net/v1/coverage');
const { supported_tlds } = await coverage.json();

IDN Support

Many ccTLDs support Internationalized Domain Names (IDNs) for non-ASCII characters:

• .de supports German umlauts (ä, ö, ü)
• .jp supports Japanese characters
• .рф is a Cyrillic ccTLD for Russia

Registration Policies

ccTLD policies can change. Some countries have:

• Blocked certain registrations for political reasons
• Changed from restricted to unrestricted (or vice versa)
• Implemented new verification requirements

SEO and ccTLDs

Search engines treat ccTLDs as geographic signals. A .de domain signals German relevance to Google. For international sites, this can be:

For global reach, gTLDs like .com or .dev are often preferred, with hreflang tags for internationalization.