Open era or Open Era may refer to:

• Open Era, the period in tennis since 1968 where professionals can compete in Grand Slam tournaments
• Open era sometimes refers to Mikhail Gorbachev's period of glasnost and perestroika in the Soviet Union

Open era or wide-open era, may also refer to:

• Open range era of the American Old West when cattle were allowed to roam freely in many states
• Early 20th century in many U.S. communities when gambling, prostitution, and/or other vices were tolerated by local governments. Among these communities were:
  • Galveston, Texas
  • Hot Springs, Arkansas
  • Atlantic City, New Jersey