Kōpuaranga, until 1906 called Dreyerton, is a rural locality[3] in the Wairarapa region of New Zealand's North Island, between Masterton and Mauriceville.

The name Kōpuaranga comes from Māori words meaning 'deep hole' and 'shoal of fish'.

In 1876 a Post Office was opened, named Opaki, however the settlement's name was changed to Dreyerton[6] in 1881,[5] after Danish interpreter Alexander Svend Dreyer,[6] who had accompanied the pioneers and conceived the idea for a township.

In December 2019, the approved official geographic name of the locality was gazetted as "Kōpuaranga".

[9] Kōpuaranga statistical area covers 458.04 km2 (176.85 sq mi).