Guides
Country Code Guides
Step-by-step help for reading calling codes, ISO codes, ccTLDs, and complete international numbers.
Guide
How Country Calling Codes Work
Understand the ITU-T E.164 numbering plan and how country codes are assigned and dialed.
6 min read
Guide
ISO Country Codes Explained
The difference between ISO alpha-2, alpha-3, and numeric codes and when to use each one.
5 min read
Guide
How to Dial Internationally
A practical sequence for dialing international numbers from any phone.
4 min read
Guide
Country Code vs. Area Code
Learn how country calling codes and area codes work together in an international number.
4 min read
Guide
What Is a Country Code?
A plain-language introduction to country codes, including calling codes, ISO codes, and ccTLDs.
4 min read
Guide
What Is a ccTLD?
Understand country-code top-level domains and why .uk, .de, and .jp differ from generic domains.
4 min read
Guide
How Time Zones Work
A practical guide to UTC offsets, IANA time zone identifiers, and daylight saving time.
5 min read
Guide
IATA vs. ICAO Airport Codes
Learn the difference between three-letter IATA codes and four-letter ICAO codes used at airports.
5 min read
Guide
How Postal Codes Work Around the World
A country-level guide to postal and ZIP code formats, examples, and validation patterns.
5 min read