A self-described "nerd with a love of the outdoors" has won the Miss Auckland competition, beating, among others, Max Key's girlfriend Amelia Finlayson.

Karla de Beer, a former student at Macleans College, took the top prize on Saturday night and will represent Auckland at the Miss World New Zealand competition.

The pageant focused on charity fundraising and in the lead-up to the competition de Beer held a sausage sizzle at her old workplace Bunnings Takanini to raise money for Riding for the Disabled.

Instagram/Amelia_Finlayson Amelia Finlayson is competing in Miss Auckland.

In the lead up to the event, all eyes were on Amelia Finlayson, who ended up placing fourth.

The girlfriend of the Prime Minister's son told the audience Miss Auckland had helped her "work towards who I want to be, and that's key".

The finalists were fundraising leading up to the big night for the event's chosen charity Koru Care New Zealand, an organisation that makes "dreams come true for sick and disabled children".

@MAXKEY_/INSTAGRAM Amelia Finlayson, with boyfriend Max Key, during their much talked about Hawaii holiday.

Finlayson has also helped out Torbay Kindergarten as a personal charitable effort.

On Finlayson's devoted "Amelia Finlayson Miss Auckland Finalist 2015" Facebook page, she said she recently turned 18.

She said she celebrated in a hotel room with "her girls" and then woke up to a surprise day spa retreat from her "special boyfriend".

Instagram/Amelia_Finlayson Amelia Finlayson is competing in Miss Auckland.

"Together we celebrated by having a massage and a lovely day spa!"

Finlayson achieved some minor celebrity in July when Key, 20, posted a video of the pair on social media.

Titled Max Key & Amelia Finlayson in Summer Paradise the four minutes and 27 seconds of footage is described on YouTube as: "A journey into myself and Amelia's teenage years."

In her bio on the Miss Auckland page, Finlayson said she would like to "become a TV presenter and producer".

Describing why she loved the city, she said: "Auckland to me is the City of Sails with the most beautiful beaches from the east to the west coast.

"Auckland gives you freedom, safety and has plenty of incredible places to discover."

The Miss Auckland website said the evening was about celebrating the young women and their contribution to the Auckland community.

Judges were looking for the ultimate ambassador for Auckland city - "someone who is a fantastic role model, confident in herself and captures what our city represents as a collective people".

The winner, de Beer, will represent the Auckland region at Miss World New Zealand in April.