What this looks up
For any country in the table, four codes are shown side by side:
- ISO 3166-1 alpha-2: two-letter code (US, GB, JP). What you see in URLs, top-level domains (.us, .gb, .jp), and most software UIs.
- ISO 3166-1 alpha-3: three-letter code (USA, GBR, JPN). Used by the Olympics, FIFA, ICANN, and many government systems.
- ISO 3166-1 numeric: three-digit code (840, 826, 392). Used in banking systems, customs declarations, and statistical agencies (UN).
- International dialing code: phone country code (+1, +44, +81). The ITU-T E.164 standard.
Search is forgiving, type the country name (full or partial), any of the codes, or the dial code. Empty search shows all countries alphabetically.
When you actually need each format
alpha-2 is what you’ll use 90% of the time. Forms that ask for “country” usually mean alpha-2. URLs with country prefixes (e.g., shopify.com/en-US) use alpha-2 country codes paired with ISO 639 language codes.
alpha-3 appears in:
- Sports broadcasting and news (USA wins gold)
- Some financial settlement systems
- Government documents
- ICAO airport codes (sort of, ICAO is different but related)
Numeric appears in:
- Banking systems (SWIFT, ACH)
- ISO 4217 currency code lookups
- UN statistical agencies
- VAT systems (in conjunction with country)
Dial codes are for telecom systems. The number after + is the country code; what follows is the area/subscriber code. Note that some countries share dial codes (US, Canada, Caribbean nations all use +1, distinguished by the next 3 digits).
Edge cases the table handles
- +1 is shared. US, Canada, Dominican Republic, and several Caribbean countries all use +1. The lookup shows them all with +1 dial code; the ISO codes distinguish them.
- +7 is shared. Russia and Kazakhstan share +7. Different ISO codes, same dial code.
- DR Congo vs Republic of Congo. “Congo” alone is ambiguous, there are two countries. The table uses “DR Congo” (formerly Zaire) for the larger one. The smaller “Republic of Congo” isn’t in this 120-country list but is CG / COG / 178 / +242 if you need it.
What’s not in the lookup
The table covers ~120 countries, the most populous and economically significant. Skipped:
- Micronations (Vatican City, Andorra, Monaco, etc.), included in the official ISO 3166-1 list (~250 entries) but rarely needed
- Disputed territories: Taiwan, Western Sahara, Palestine, Kosovo are politically sensitive; their ISO codes vary by which body you ask
- Antarctica: ISO code AQ exists but no permanent residents
- Subnational territories: Hong Kong is included as a special case (it has its own ISO code despite being part of China). British Virgin Islands, US Minor Outlying Islands, etc. are not.
For a complete ISO 3166-1 list (250+ entries), the official ISO website or Wikipedia have the full reference.
Frequently asked questions
What’s the difference between ISO 3166-1 and ISO 3166-2? ISO 3166-1 is country-level (US). ISO 3166-2 is subdivision-level (US-CA for California). This lookup is country-level only.
Why doesn’t the EU have a code? The EU isn’t a country. It does have a non-standard code “EU” used informally, but ISO 3166 specifically excludes supranational entities.
Can I trust dial codes for VoIP? The dial codes here are accurate per ITU-T E.164. VoIP providers may have their own quirks (some treat +1 as “domestic” only for US numbers and require a different prefix for Canada).
Why are some country names different from what I’m used to? ISO uses official short-form English names. “Russia” instead of “Russian Federation.” “DR Congo” instead of “Democratic Republic of the Congo.” For exact official names, see the ISO 3166-1 list.