Steve Kropla maintains a comprehensive list of international dialing codes. The table provides a list of all the countries in the world, their country dialing code (the prefix you would use to call a number in that country eg. The US is +1, while the UK is +44) and their international and local direct dialing codes (the prefix you would use in a country to dial internationally or locally – the international direct dialing code in South Africa is 09, while the local direct dialing code is 0). Thus to phone the US from South Africa, you would dial 09-1-number, while to phone the UK, you would dial 09-44-number.
In addition, you can click on any country in the table and get a comprehensive list of the main city dialing codes in that country (including mobile/cellular operators).
Alternative sources
International numbering plans
At International Numbering Plans, a site that strives to make international dialing databases more accessible, you can access international area code lists and get instructions on how to dial internationally from various countries.
Country calling codes
This site combines some of the features of Steve Kropla’s site and that of International Numbering Plans. Click here to visit the site. It is worth a visit if the other two can’t help you. It has a useful reverse look-up, if you know the country code, but don’t know what country it refers to – reverse look up.