Korean Phone Number Formatter
Normalize messy Korean phone numbers into the standard hyphenated format in bulk—mobile, Seoul 02, area codes, 070, 0505, and 1588-style numbers. Everything runs in your browser.
FAQ
Which number types are recognized?
Mobile (010…), Seoul (02), 3-digit area codes, VoIP (070), safe numbers (0505), and 15XX/16XX/18XX service numbers—regardless of dots, spaces, or parentheses.
Can I clean an Excel contact column?
Yes—paste the column, copy the result back. If Excel stripped leading zeros, format the column as text first.
Are the numbers uploaded?
No. Everything happens entirely in your browser and nothing is stored.
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