The former MK Dons midfielder joined Newport on a two-year deal last summer from Barnet and made 27 appearances.
The 27-year old was out of favour with previous boss Graham Westley, but played a key role in the Exiles' escape from League Two relegation.
Randall is understood to be close to agreeing a deal to sign for a fellow League Two club.
Meanwhile, former Newport striker Ryan Bird, released by the Exiles this summer, has joined non-league Dover Athletic.
Newport County midfielder Mark Randall has left the club after having his contract terminated by mutual consent.