Test your fax number

Select the country, enter the number: the answer is immediate.

A correct fax number designates a landline, written according to local rules: in Belgium, eight digits preceded by a 0, for example 02 475 12 34. Faxeroo applies here, identically, the check from its send form in seven countries (Belgium, Canada, Germany, Spain, France, Italy, Portugal), flags mobiles as well as dialled-in-twice codes, then gives the international notation.

Instant check

e.g. 5145551234 — Ten digits in total: three for the region, seven for the subscriber, without the leading 1

Why check a number before sending

Most failed faxes fail on the number, rarely on the document or the network: a digit added when copying from an email signature, a dialling code duplicated by a copy-paste, or a mobile mistaken for the secretariat's line. At the other end, no fax machine picks up, and the send exhausts itself in errors after several attempts.

Each country follows its own rules. On the Belgian side, a national number opens with a 0 and runs to nine digits for a landline, ten for a mobile starting 04. Germany gives its urban dialling code two to five digits after the 0. In Italy, the leading 0 is kept even from abroad, whereas it disappears in Belgium, France and Germany. The tool knows these rules and shows both notations: the one to type in the Faxeroo form, in national format, and the E.164 international notation, which is what you use with another fax machine or another provider.

The check targets the form of the number, not its actual existence: a correct notation can hide a disconnected line or one connected to a plain telephone. If in any doubt, take the number the organisation officially displays — website or recent letter.

Fax numbers: frequently asked questions

Is the number I enter kept?
No. It is examined at the time of the check and then forgotten: nothing is stored, no fax goes out, no call is made to that line.
Why are mobiles excluded?
A fax requires a landline connected to a device or a specialist server. A mobile is not built to capture that signal: the call would end in a ring or a voicemail, never in a printed page.
Does a valid number guarantee delivery?
Its form is correct, which rules out the majority of failures. What remains is whether the line exists and reaches a powered-on device: if the send fails all the same, have the number confirmed by the recipient.

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