DievioPhone Number Validator & E.164 Formatter
Check phone-number format against international numbering metadata and convert valid-format numbers to E.164. Process one number or a newline-separated list.
How to use this tool
- Select the default country for numbers without a calling code.
- Paste one phone number per line.
- Review format status and export the formatted numbers.
A worked example
Input
(202) 555-0123 · Default country: United States
Output
+12025550123 · US · Valid numbering format
The default country is used for national numbers. Numbers with an explicit international calling code are parsed using that code.
What the result means
E.164 keeps a leading + and international calling code. Valid numbering format means the digits match numbering metadata; it does not mean the number is active or belongs to the intended contact.
Valid numbering format does not prove that a number is assigned, active or owned by a particular person. Numbering metadata changes over time.
Frequently asked questions
What is E.164 formatting?
E.164 represents an international phone number with a leading +, country calling code and national number. For example, a US national number can become +12025550123.
Does a valid result mean the phone is active?
No. The check uses numbering-plan metadata, not a live carrier or ownership lookup. A number can match the format without being assigned, reachable or owned by the person in your file.
Is this free, and are my inputs uploaded?
Use this tool without an account, subscription or credits. Processing and file exports run in your browser; the tool does not upload your inputs or send emails. Clear inputs to remove the current data. Inputs are not saved when you reload the page.
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