What this tool checks
This is a basic validator: it verifies a number's format rather than whether the number is actually active on a network or registered on WhatsApp. That distinction matters - real "is this number on WhatsApp?" checks require a paid provider API. For most use cases a format check catches the vast majority of mistakes.
Checks performed (all local)
- Digits only - non-digit characters are stripped and flagged.
- E.164 length - the ITU E.164 standard allows at most 15 digits including the country code, and the tool also treats fewer than 7 as too short.
- Country code match - longest-prefix match against the dial codes of 220+ countries.
- Subscriber length - checks the national part fits the expected length for the detected country.
- Trunk prefix (leading 0) - warns if you included a domestic trunk prefix that needs stripping.
- Canonical formats - outputs E.164 and a wa.me-ready string.
What this tool does not do
- No HLR / MNP lookup - it won't tell you the carrier or whether the number has been ported.
- No "is this on WhatsApp?" check - those require an authorised WhatsApp Business API partner.
- No SMS pings - we never contact the number.
How to check a number
- Either pick a Country and type just the national number, or leave the country empty and paste the full number starting with
+.
- Click Validate or press Enter. Once a number is in the box, the result also refreshes as you type or change the country.
- Read the summary at the top of the result: green means every check passed, amber means the number was understood but something needs attention, and red means no country code could be found.
- Copy the E.164 form for databases and SMS tools, or the wa.me form for chat links. Test on WhatsApp opens a chat with the number, and the other buttons carry it to our link and QR generators.
When the input starts with +, the country is detected from the number itself and your country selection is ignored. Without a +, a selected country always wins and the whole input is treated as the national part.
Worked examples
- India selected, input
098765 43210 - the space is stripped, the leading 0 is flagged as a trunk prefix and removed, and the 10 remaining digits match India's usual mobile length. Output: +919876543210 (12 digits in total) and 919876543210 for wa.me.
- No country, input
+44 07911 123456 - 44 is matched as the United Kingdom, the 0 after the country code is flagged, and the cleaned national number has 10 digits. Output: +447911123456.
- India selected, input
98765 4321 - only 9 digits. The format is parseable, so the result is amber with a note that India's typical length is 10.
Why E.164 matters
E.164 is the international numbering plan behind every phone number: a plus sign, a country code of one to three digits, then the national number, with no spaces and no trunk 0. Storing numbers in this one form avoids duplicates such as "09876543210" and "+91 98765 43210" being treated as two people, and it is the form that messaging APIs, SMS gateways and wa.me links expect.
Limits to keep in mind
- Shared country codes - several countries share +1 (the United States, Canada and much of the Caribbean) and +7 (Russia and Kazakhstan). The number itself is still correct, but the country label shown may be the other member of the group. Caribbean area codes such as 1876 for Jamaica are recognised.
- Lengths are typical, not exact - the expected lengths come from common mobile and landline formats. A number of the right length can still be unassigned, and a few valid numbers fall outside the usual range.
- One number at a time - for a list, validate a sample by hand and use a phone-number library in your own code for bulk cleaning.
Privacy
Validation runs entirely in your browser. The number is not sent to us, logged, or cached anywhere except the current tab.
