Czechia (+420 / 00420): 9 digits
Locals write 601 234 567. An API wants +420601234567. Paste any Czechia number below to see it normalised, validated, and identified.
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Since the engine is the same one the API runs, a key does not buy you a better answer. It buys volume, bulk jobs and a signed receipt.
How Czechia numbers are written
- Country calling code
- +420
- Dialled from abroad
- 00420 (011 420 from the US and Canada)
- ISO country code
- CZ
- National number length
- 9 digits
- Trunk prefix
- None
- Written locally
- 601 234 567
- E.164 format
- +420601234567
What +420 means
+420 is the country calling code for Czechia. The same code is written 00420 when you dial out from most of Europe, Africa and Asia, and 011 420 from the US and Canada. All three reach the same place: only the exit code in front of it changes. Czechia uses no trunk prefix, so the national number follows the code unchanged.
Mobile numbers
No trunk prefix. Mobiles start with 6 or 7.
Converting to E.164
Take the number as written locally (601 234 567), add the +420 prefix (there is no trunk digit to remove). The result is +420601234567: no spaces, no dashes, no parentheses. Store that, and format for display only when you show it to a human.
Why not do it with a regex
A pattern that matches Czechia numbers today breaks the moment a new mobile range is allocated, and it cannot tell you whether the number is actually assigned. The tool above runs the same numbering-plan engine as our phone validation API, so it also reports line type and region rather than just shape.
That is how a Czechia number is written. Whether a whole list is worth dialling is the free call list cleaner, or check one number on the spam phone checker.