You could use a character class ([./-]) so that the seperators can be any of the defined characters
var dateReg = /^\d{2}[./-]\d{2}[./-]\d{4}$/
Or better still, match the character class for the first seperator, then capture that as a group ([./-]) and use a reference to the captured group \1 to match the second seperator, which will ensure that both seperators are the same:
var dateReg = /^\d{2}([./-])\d{2}\1\d{4}$/
"22-03-1981".match(dateReg) // matches
"22.03-1981".match(dateReg) // does not match
"22.03.1981".match(dateReg) // matches