4 Top-level domains and their allocation
What are top-level domains?
Top-level domains (TLDs) are the last part of a domain name – the part after the last dot. In the address www.example.com, ‘.com’ is the top-level domain. TLDs form the highest hierarchical level in the Domain Name System (DNS) and are essential for the organisation of the Internet.
Every domain name follows a hierarchical structure that is read from right to left:
www.kbw.ch
- TLD: .ch (Switzerland)
- Second-level domain: kbw
- Subdomain: www
Types of top-level domains
1. Generic top-level domains (gTLDs)
Generic TLDs are not country-specific and can be registered worldwide:
- .com – Commercial (originally for companies)
- .org – Organisation (for organisations)
- .net – Network (originally for network providers)
- .edu – Education (only for accredited educational institutions)
- .gov – Government (only for US government agencies)
- .mil – Military (only for the US military)
2. Country Code Top Level Domains (ccTLDs)
Each country is assigned a two-letter code according to ISO 3166-1:
- .ch – Switzerland (Confoederatio Helvetica)
- .de – Germany
- .fr – France
- .uk – United Kingdom
- .us – United States
There are a total of 249 ccTLDs for countries and territories.
3. New Generic Top Level Domains (ngTLDs)
Since 2013, over 1,200 new TLDs have been introduced:
- .shop, .blog, .app
- .berlin, .paris, .swiss
- .google, .apple (brand TLDs)
The registry: ICANN and IANA
The Internet Corporation for Assigned Names and Numbers (ICANN) is the central organisation for the administration of the domain name system. It was founded in 1998 and is headquartered in Los Angeles, USA.
The Internet Assigned Numbers Authority (IANA), a division of ICANN, manages the root zone of the DNS. This contains all TLDs and their associated name servers.
Hierarchy of allocation
- ICANN/IANA → Manages all TLDs
- Registry → Operates a specific TLD (e.g. SWITCH for .ch)
- Registrar → Sells domains to end customers
- Registrant → The domain owner
The allocation process for new gTLDs
Phase 1: Application
Organisations can apply to ICANN for new TLDs. The last major application round was in 2012:
- Application fee: USD 185,000
- Application period: 4 months
- Applications received: 1,930
Phase 2: Evaluation
ICANN reviews each application for: - Technical competence - Financial stability - No trademark infringements - Public interest
Phase 3: Delegation
After successful review, the TLD is entered into the root zone. The entire process typically takes 18-24 months.
Costs and fees
For registry operators
- Annual ICANN fee: USD 25,000 per TLD
- Transaction fee: USD 0.25 per domain registration
- Operating costs: Technical infrastructure, personnel, marketing
For end customers (examples)
- .ch domain: CHF 10-20 per year
- .com domain: CHF 15-25 per year
- Premium ngTLDs: CHF 50-500+ per year
Special regulations
Restricted TLDs
Some TLDs have special registration conditions:
- .edu – Only for accredited US universities
- .museum – Only for museums
- .aero – Only for the aviation industry
- .swiss – Connection to Switzerland required
Internationalised domain names (IDN)
Since 2010, TLDs in non-Latin scripts have been possible:
- .中国 (China)
- .рф (Russia)
- .ελ (Greece)
Statistical overview
As of 2025, there are:
- Active TLDs: ~1,500
- Registered domains worldwide: ~370 million
- Largest TLD: .com with ~160 million domains
- Swiss .ch domains: ~2.5 million
The distribution follows a power law: the 10 largest TLDs host around 75% of all domains.
Significance and outlook
Top-level domains are more than just technical designations – they are digital identities. A .ch domain signals Swiss origin, while a .edu domain stands for education. With the continuous expansion of the Internet, the importance of a well-thought-out TLD structure is also growing.
The next ICANN application round for new gTLDs is planned for 2026. Experts expect another 500-1,000 new TLDs, including an increasing number of city and brand names. The challenge will be to maintain a balance between innovation and clarity.