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Random Fax Number for Testing

When you need to test your fax machine and don't have anyone to send to, dialing a random number might seem like the easiest option. It's not — and it can cause problems you didn't expect. Use a dedicated test number instead.

Fax Test Numbers

Send your fax to one of these numbers & see it appear below shortly
(click to copy)

or in international format:

Why random fax numbers don't work for testing

  • Most numbers aren't fax lines. A random 10-digit number will almost certainly ring a phone, go to voicemail, or hit a disconnected line. Your fax machine will report an error, and you won't know whether the problem is your machine or the number you dialed.
  • No way to verify delivery. Even if a fax machine happens to answer, you have no way to confirm your document was received correctly. Was it legible? Did all pages arrive? You'll never know.
  • You might fax a stranger. Sending an unsolicited document to someone's private fax line is, at best, a waste of their paper and ink. At worst, you could be sending sensitive test documents to an unknown recipient.
  • Long-distance charges apply. If the random number you dial is long-distance or international, you'll be charged for the call — even if the fax fails.

What a valid fax number looks like

Fax numbers use the same format as phone numbers because they share the same telephone network. The difference is what answers the call — a fax modem instead of a person.

  • US / Canada: +1 (XXX) XXX-XXXX — 10 digits after the country code
  • UK: +44 (0XX) XXXX XXXX — length varies by area code
  • Australia: +61 (0X) XXXX XXXX
  • International format: Always start with + and the country code when dialing from abroad

Better alternatives to a random number

Option Confirms sending Confirms receiving Free Results
Faxbeep test numbers Yes No Yes Online in 1–2 min
HP echo service (1-888-473-2963) Yes Yes Yes ~10 min
Canon echo service (1-855-392-2666) Yes Yes Yes ~10 min
Fax a colleague or friend Yes Ask them Yes Varies
Random number No No Maybe Never

Receiving unwanted faxes?

If you're on the other end — receiving faxes you didn't ask for — here are the most common causes and what you can do:

  • Wrong number. The sender may have misdialed. This is the most common cause of unexpected faxes.
  • Outdated recipient info. Your fax number may have previously belonged to someone else, and senders haven't updated their records.
  • Spam or fax blasting. Unsolicited marketing faxes are illegal in many countries. In the US, you can report junk faxes to the FCC.
  • Someone testing their machine. If the fax looks like a test page (generic text, a single page, no cover sheet), someone probably dialed your number while testing their fax machine — possibly through a service like Faxbeep.

To stop unwanted faxes, check your fax machine's manual for number-blocking features, or contact your phone provider about call filtering options.

FAQ: Random Fax Numbers

No. Fax numbers must be real, active telephone lines connected to fax equipment. A randomly generated number won't connect to anything useful — it's no different from dialing a made-up phone number.

If a person or voicemail answers, your fax machine will fail to negotiate a connection and report an error. If another fax machine happens to answer, your document will go through — but to a stranger, with no way for you to verify it arrived correctly.

Same format, same telephone network, different equipment. A fax number is just a phone line connected to a fax machine or fax modem instead of a telephone. You can't tell the difference from the number alone.

No. Unlike phone directories, there's no public listing of fax numbers. If you need a number to send a test fax to, use a dedicated test service like Faxbeep.

Test your fax now

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