Fax number checker
Pick the country, paste the number and see straight away whether it will go through.
A usable fax number is a landline written in the format of its country: in Canada, a three-digit area code followed by seven digits, such as 416 555 0134. This free tool runs the exact check used by the FaxTelecom sending form for Canada, Belgium, France, Germany, Spain, Italy and Portugal, flags mobile ranges and country codes typed twice, and shows the international form.
Test a number
Why test a number before you fax
Most failed faxes have nothing wrong with the document or the network. The problem is the number: an extra digit copied from an email signature, a country code pasted twice, or a cell number mistaken for the office line. The machine at the other end never answers, and the send ends in an error after several attempts.
Every country follows its own rules. Canadian numbers are ten digits with no leading zero, and the 1 in front is a long-distance prefix rather than part of the number. Belgian landlines are nine digits starting with 0, while mobiles start with 04. Italy keeps its leading 0 even when dialled from abroad, whereas Belgium, France and Germany drop it. The checker knows these rules and shows you two versions: the national one to type into the FaxTelecom form, and the E.164 form that fax machines and other services expect.
The test covers the shape of the number, not whether it is in service: a well-formed number can be disconnected or ring a telephone. When the stakes are high — a filing with the CRA, a prescription to a pharmacy — take the number from the organisation’s official website or from the latest letter you received from them.
Questions about checking fax numbers
- Is the number I enter stored anywhere?
- No. It is checked when you press the button and then discarded. Nothing is kept, no fax is sent and no call is placed to that number.
- Why are mobile numbers rejected?
- Fax relies on a fixed line connected to a fax machine or a fax server. A mobile phone cannot decode that signal, so the call would end in a ring tone or a voicemail, never in a printed page.
- Will a valid number always receive the fax?
- It has the right shape, which rules out most failures. The line still has to be in service and connected to a machine that is switched on; if a send fails anyway, confirm the number with the recipient.
Where to go next
Hand-picked pages to help you prepare, send or prove your fax.
- Check a country’s calling code, its common prefixes and the expected number length before faxing abroad.
- Pick a destination to see its country code and expected number format, then start your fax to a landline.
- Choose your PDF and get the page count and price in a second — nothing is uploaded.
- A handful of fields, one PDF to download, placed at the front of your fax.
- Practical answers for preparing, sending and tracking a fax with FaxTelecom.
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