Aranui is one of the eastern suburbs of Christchurch. It is a low socio-economic area. In its early years, Aranui grew along Pages Road, the suburb's main road. Aranui soon became a working-class suburb. There are also areas of light-industrial premises in Aranui.

The suburb grew rapidly between 1945 and 1951. The area is predominantly residential with pockets of light industry. A large number of state houses were built in the suburb after the World War II. There are shops and service facilities at the intersection of Breezes Road and Pages Road and a smaller retail precinct centred on Hampshire Street. It is served by the composite school Haeata Community Campus in Wainoni, which was created by a merger of four schools in 2017. Aranui is part of the Christchurch East parliamentary electorate.

Part of the area was previously called Flemington, named after the hairdresser and tobacconist Jubal Fleming (c.1844–1903). Fleming had a subdivision at the corner of Breezes and Pages Roads, and the tram stop on Breezes Road was informally called Flemington. The post office was established in 1912 and it was named Aranui by George Kyngdon Burton (c.1859–1957), with that name then applied to the wider area. Aranui is a Māori word, with ara meaning path and nui meaning great.

In its early years, the New Brighton Tramway Company extended the Linwood Cemetery route. Land in Aranui was cheap at the time, though infertile for agriculture purposes, and transportation so that settlement in Aranui increased.

Aranui soon became a working class suburb. There are also areas of light-industrial premises in Aranui. The suburb grew rapidly between 1945 and 1951 from 404 to 1,141 dwellers. Local shopping centres were established around Christchurch, particularly in some of the neighbourhoods which had larger state-housing developments. Today, the suburb is mainly residential, though it has areas of retail businesses sited on Pages Road. There is also a smaller retail precinct centred on Hampshire Street.

A large number of state houses were built in Aranui after the World War II. Residents are still generally of low socio-economic status. In a 2020 report of the Burwood ward from Kāinga Ora, the suburb of Aranui had the highest number of state-owned houses in Christchurch.

In the 19th century, much of the area consisted of rough grass and sand hills. Today, Aranui is one of the eastern suburbs. Its eastern boundary is the Avon River. Boundary roads are Pages Road in the south, Breezes Road in the west, and Wainoni Road in the north. Bexley is located to the south of Pages Road.

Aranui and its neighbouring suburb of Wainoni are sometimes considered together. Christchurch City Council publishes a combined community profile for the two suburbs. Other suburbs nearby include New Brighton and Avondale.

The Christchurch City Council administers Aranui. The suburb is part of the Burwood Ward for Christchurch City Council local body elections. The currently elected councillor is Kelly Barber. Nationally, Aranui is part of the Christchurch East parliamentary electorate. The currently elected member of parliament is Reuben Davidson of the Labour Party. Historically, Christchurch East has supported the Labour Party in general elections and is considered one of Labour's safest seats.

Aranui covers 1.42 km (0.55 sq mi). It had an estimated population of 4,550 as of June 2024, with a population density of 3,204 people per km.

Historical population

Year	Pop.	±% p.a.
2006	4,260	—
2013	3,777	−1.70%
2018	4,200	+2.15%
Source:

Aranui had a population of 4,200 at the 2018 New Zealand census, an increase of 423 people (11.2%) since the 2013 census, and a decrease of 60 people (−1.4%) since the 2006 census. There were 1,392 households, comprising 2,106 males and 2,091 females, giving a sex ratio of 1.01 males per female. The median age was 30.0 years (compared with 37.4 years nationally), with 1,101 people (26.2%) aged under 15 years, 999 (23.8%) aged 15 to 29, 1,740 (41.4%) aged 30 to 64, and 354 (8.4%) aged 65 or older.

Ethnicities were 66.1% European/Pākehā, 29.9% Māori, 17.6% Pasifika, 3.7% Asian, and 2.0% other ethnicities. People may identify with more than one ethnicity.

The percentage of people born overseas was 13.4, compared with 27.1% nationally.

Although some people chose not to answer the census's question about religious affiliation, 53.9% had no religion, 31.8% were Christian, 2.6% had Māori religious beliefs, 0.7% were Hindu, 0.1% were Muslim, 0.2% were Buddhist and 2.1% had other religions.

Of those at least 15 years old, 153 (4.9%) people had a bachelor's or higher degree, and 1,098 (35.4%) people had no formal qualifications. The median income was $21,300, compared with $31,800 nationally. 96 people (3.1%) earned over $70,000 compared to 17.2% nationally. The employment status of those at least 15 was that 1,224 (39.5%) people were employed full-time, 363 (11.7%) were part-time, and 288 (9.3%) were unemployed.

Aranui is served by the composite school Haeata Community Campus in Wainoni, which was created by a merger of four schools in 2017. Haeata Community Campus has a roll of 570 students as of August 2024. It was created by merging Aranui School, and Wainoni School, and was built on the former Aranui High School site in 2017.

• Tusiata Avia, a poet and children's author
• Mabel Howard, New Zealand's first woman cabinet minister, was once a resident in the area.
• Keri Hulme, a novelist and poet, was educated in Aranui High School and lived in the suburb for a short period of time.
• Ladi6, singer and songwriter, grew up in Aranui.
• Scribe, rapper
• Duncan Webb, lawyer and politician

• Media related to Aranui at Wikimedia Commons
• A 2016 commentary on the suburb