Test your fax number

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

A valid fax number identifies a landline, written according to local conventions: in Belgium, eight digits preceded by a 0, for instance 02 475 12 34. Faxeroo applies the identical verification from its send form in seven countries (Belgium, Canada, Germany, Spain, France, Italy, Portugal), flags mobile numbers and repeated-dial codes, then provides the international format.

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 applies its own regulations. In Belgium, a national number begins with a 0 and contains nine digits for a landline, ten for a mobile starting 04. Germany assigns its area code two to five digits following the 0. In Italy, the leading 0 is retained even when dialling from abroad, whereas it is omitted in Belgium, France and Germany. The tool applies these rules and presents both formats: the one to enter in the Faxeroo form, in national format, and the E.164 international notation, which you use when sending to 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 needs a landline linked to a device or a dedicated server. A mobile is not designed to receive that signal: the call would simply ring or go to voicemail, never producing 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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