Check whether a Slovakia number is valid, detect its line type, and convert it to E.164, international, or national format — instantly and free. Powered by Google's libphonenumber.
| Country | Slovakia (SK) |
| Country calling code | +421 |
| Example number (international) | +421 912 123 456 |
| National format | 0912 123 456 |
| E.164 format | +421912123456 |
| RFC 3966 (tel: URI) | tel:+421912123456 |
| Example line type | mobile |
To dial a Slovakia number from abroad, start with the country code +421 followed by the national subscriber number. In E.164 — the format every SMS gateway, CRM, and payment provider expects — the same number is stored as +421912123456: a leading +, the country code, and the national number with no spaces or separators.
The interactive tool above runs entirely in your browser. For server-side validation at scale — sign-up forms, lead cleaning, SMS routing — call the API. One GET request, no SDK, works in any language.
# Validate a Slovakia number via the API curl "https://phone-validation-and-formatting.p.rapidapi.com/v1/validate?number=%2B421912123456" \ -H "X-RapidAPI-Key: YOUR_KEY" \ -H "X-RapidAPI-Host: phone-validation-and-formatting.p.rapidapi.com"
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The country calling code for Slovakia is +421. A full number in international (E.164) form looks like +421912123456.
A typical Slovakia mobile number is written +421 912 123 456 internationally, 0912 123 456 nationally, or +421912123456 in E.164 format.
Send one GET request to the Phone Validation API with the number and country code "SK". The response tells you whether it is valid, the line type, and every standard format. A free tier is available.
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