What this page does
This page helps you find the country calling code you need before you dial abroad, and turns a local number into the international format that works from any phone. It lists 29 countries in 3 regions (Asia: 12; Europe: 10; Americas & Oceania: 7). The converter above removes the domestic trunk prefix from a number you type, adds the calling code, and checks the result against the 15-digit limit. Everything runs in your browser; the number you type is never sent to a server. The codes follow ITU-T Recommendation E.164, the international numbering plan, but this is a quick reference, not a complete directory of every country and territory.
How an international number is built
E.164 describes a public telephone number as a country code (one to three digits) followed by the national significant number, and the two parts together may not exceed 15 digits. Country codes are allocated so that no code is the beginning of another one. That is why a telephone exchange can read the first few digits and know where to route the call without waiting for the rest. The converter enforces the same limit: if the country code plus the digits you type go past 15, it asks you to check the number.
In this list, the length of the code is the only thing that varies, and the table below counts it directly from the data on this page.
| Digits in country code | Countries listed | Which ones |
|---|---|---|
| 1 | 3 | Russia, United States, Canada |
| 2 | 23 | South Korea, Japan, China, Thailand, Vietnam, Singapore, India, Philippines, Indonesia, United Kingdom, France, Germany, Italy, Spain, Netherlands, Switzerland, Turkey, Sweden, Mexico, Brazil, Argentina, Australia, New Zealand |
| 3 | 3 | Taiwan, Hong Kong, United Arab Emirates |
A code is not always one country. On this page +1 is shared by United States and Canada. The +1 code belongs to the North American Numbering Plan, which also covers other countries and territories, and they are told apart by the three-digit area code that follows. So the calling code alone does not tell you which country a call really belongs to, and it says nothing about where the caller is standing.
The dialing sequence, step by step
Dialing from a landline follows three parts: international access code, country code, then the national number without its trunk prefix. The access code is set by the country you are calling from. The United States and Canada use 011, many European countries use 00, and Japan uses 010. Because the code depends on the caller's country, a printed number almost never includes it. Instead, numbers are written with a plus sign: +44 20 7946 0000. On a mobile phone, the plus sign stands for whatever access code the local network needs, so a contact saved in that form works from home, from a hotel abroad or on a local SIM without editing.
Do not type both the plus sign and an access code. "011 +44 ..." is a common slip, and it normally just fails.
The leading zero problem
Many countries write their numbers with a leading 0 that exists only for dialing inside that country (the "trunk prefix"). It tells the switch that you are leaving the local area. An international call has already announced that, so the 0 is dropped. A London number written 020 7946 0000 at home becomes +44 20 7946 0000 abroad, and a Korean mobile number 010-1234-5678 becomes +82 10 1234 5678. North America is different: its trunk prefix is a 1, and the +1 already covers it. Russia's domestic prefix is 8, and Italy is a notable exception where landline numbers keep the leading 0 even in international form. The table is generated with the same rule the converter uses.
| Country | As written locally | International format | What changed |
|---|---|---|---|
| United Kingdom | 020 7946 0000 | +44 2079460000 | London 020 becomes +44 20; the 0 disappears. |
| South Korea | 010-1234-5678 | +82 1012345678 | Mobile prefix 010 loses its 0 and continues as 10. |
| Japan | 03-1234-5678 | +81 312345678 | Tokyo area code 03 loses the 0. |
| United States | 1 (212) 555-0123 | +1 2125550123 | The long-distance 1 is dropped because +1 already says it. |
| Italy | 06 1234 5678 | +39 0612345678 | Italian landlines keep the leading 0. |
| Australia | 0412 345 678 | +61 412345678 | Mobile 04 becomes +61 4. |
Business cards in some countries print the zero in brackets, as in +44 (0)20 7946 0000. Read this as a hint: the (0) is for people dialing inside the country, and you leave it out when you dial from abroad.
Two worked examples
Example 1: calling a Japanese office from the US. The local number is 03-1234-5678. Remove the 0, giving 3-1234-5678; prepend Japan's code +81; the international form is +81 3 1234 5678, or +81 312345678 without spaces. From a US landline you would key 011 81 3 1234 5678. The total length is 2 (country code) + 9 = 11 digits, comfortably under 15.
Example 2: giving your US cell number to a colleague in Italy. Your number is (212) 555-0123. Write it as +1 212 555 0123: country code 1, then the ten digits. Do not add a trunk 1 after the plus, as in +1 1 212 ..., because the plus-one already stands for it. Your colleague saves it as written and can call from anywhere.
Common mistakes and limits of this tool
- Keeping the trunk 0. "+44 020 7946 0000" often does not connect. Italy's landlines are the well-known exception, where the 0 stays.
- Mixing the plus sign with an access code. Use one or the other.
- Assuming a calling code equals one country. +1 and +7 each cover more than one country, and some codes belong to territories or to services that are not tied to a place at all.
- Trusting the code as proof of origin. Internet calling, number porting and spoofing mean a call showing a foreign number may come from elsewhere. If you do not know the caller, do not return an unfamiliar international call.
- Special rules not covered here. Some countries add extra digits for mobile numbers or have changed their numbering plan over time. For these, the converter output may be wrong, so confirm with the destination's carrier or an official source before relying on it for anything important.
- Coverage. Only the 29 countries listed here are included. For others, consult the ITU's published list of country codes or a local directory.
This tool does not look up prices, carrier rules or roaming plans. Per-minute rates vary widely between carriers and apps, so check your own plan before a long call.
Putting the result to work
Store every foreign contact in plus format from day one: "+" + calling code + number without the trunk prefix. When you give your own number to someone abroad, do the same. Use the copy button to paste the result straight into a contact card, an email signature or a booking form. Before you call, check the other person's local time; calling at 3 a.m. is a quick way to turn a useful number into an unwelcome one. The World Time Converter and theWorld Timezone Converter show the current time in the destination, and if you are flying there, theJet Lag Calculator and theTravel Packing Checklist cover the other side of the trip.
Frequently Asked Questions
Why do the US and Canada share the same country code?
The two countries belong to one shared system, the North American Numbering Plan, so both use +1. The three-digit area code that follows separates the regions. From the number alone it is hard to tell whether a call is American or Canadian.
How do I write my mobile number for someone abroad?
Remove the leading trunk prefix if your country has one and add your calling code with a plus sign. A Korean number 010-1234-5678 becomes +82 10 1234 5678, and a US number (212) 555-0123 becomes +1 212 555 0123.
Can I dial 00 or 011 instead of the plus sign?
Only if that is the access code for the country you are calling from. The United States and Canada use 011, many European countries use 00, and other countries differ. The plus sign is safer on a mobile phone, because the network substitutes the right code for wherever you are.
Why are some country codes one digit and others three?
The system is a prefix code: no code begins another code, so the exchange can decide the route after reading only the first digits. The converter and the table above count the lengths from the listed data.
What is the longest an international number can be?
E.164 limits the country code plus the national number to 15 digits. The converter warns you when the total exceeds this, which usually means a typo or an extra prefix.