When establishing the fax phone character limits, consideration was made for faxing international locations, using calling cards, and other conditions that required long field lengths. The limits are:
Fax Number field limit - 126 characters (visible characters - 25)
DialCallee string limit - 100 characters
From a user perspective the limit is less than 100 characters, somewhere between 95 to 97, as the DialCallee string limit includes characters the fax driver places in the string for specifying Pulse or DTMF (Touch-Tone) dialing, possible DTMF symbols sent to a telephone exchange, pauses, and a character requesting the fax card to wait for dial tone or not.
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