How the Success Index (NZ) works
A transparent, reproducible way to compare every New Zealand school using only official data. No surveys, no paid placements, no black box.
Data sources
The New Zealand Success Index combines the Ministry of Education's Equity Index (EQI), which measures the socio-economic barriers a school's students face, with roll size and growth, and, for secondary schools, school-leaver NCEA Level 2 and University Entrance attainment. Lower EQI numbers indicate fewer barriers; the index rewards both low-barrier communities and strong attainment relative to barriers.
- Ministry of Education โ Schools Directory (CC BY 4.0)
- Ministry of Education โ School leaver attainment (Find a school) (CC BY 4.0)
The current dataset covers 2,564 schools, of which 2,406 receive a score and 2,045 are ranked. Data was retrieved on 8 October 2026.
The components
Each school is compared only with schools of the same type across New Zealand. For each component we convert the raw value to a percentile within that type, then combine the percentiles with these weights:
| Component | Weight | Raw measure | Why it matters |
|---|---|---|---|
| Equity Index (fewer barriers is higher) | 45% | Equity Index (EQI) (lower is better) | Ministry of Education EQI, 344 (fewest barriers) to 569 (most). |
| Roll size | 10% | Total roll | Total school roll; larger rolls support broader programmes. |
| Roll growth (5 years) | 15% | Roll growth (5 yrs) | Change in roll over five years. |
| School leavers with NCEA Level 2+ | 20% | Leavers with NCEA Level 2+ | Percentage of school leavers who left with at least NCEA Level 2 (Ministry of Education school leaver data), secondary schools only. |
| School leavers with University Entrance | 10% | Leavers with University Entrance | Percentage of school leavers who left with the University Entrance award, secondary schools only. |
Adjustments
- Missing components are left out and the remaining weights are rescaled, so a school is never penalised for data that is not published for its type.
- Small schools: components marked as size-sensitive are shrunk toward the median for schools under 300 students, and schools with fewer than 60 students are scored but not ranked.
- Excluded types: Special School, Specialist School, Teen Parent Unit, Correspondence School, Activity Centre are listed but not scored.
- Required data: a school needs a published Equity Index (EQI) to be scored.
Bands and ranks
The combined score is placed on a 0โ100 scale and labelled by percentile within school type: Top 5%, Top 10%, Top 25%, Top 50% or Lower 50%. Ranks are computed nationally, within each region and within each territorial authority, always within school type.
Known limitations
- The Equity Index describes the student community, not teaching quality.
- NCEA and University Entrance figures are for school leavers (all students who left in the year), so schools that retain students to Year 13 tend to score higher.
- Primary and intermediate schools have no published attainment data, so their index is community- and roll-based.
Attribution
School directory, Equity Index, roll and school-leaver attainment data: New Zealand Ministry of Education (Education Counts), Creative Commons Attribution 4.0. The Success Index is produced by Success Tutoring and is not endorsed by either agency.
Frequently asked questions
Is the Success Index (NZ) a measure of school quality?
No. It summarises published data about a school community and, where available, attainment. These correlate with academic results but do not measure teaching quality, wellbeing or culture.
Why are small schools not ranked?
Schools with fewer than 60 students have growth and attainment figures that swing dramatically with a handful of enrolments. They receive a score on their profile page but are excluded from ranking tables.
How often is it updated?
Automatically whenever the source agencies publish new data, plus whenever we improve the methodology. The data year (2026) is shown on every page.
Can a school pay to improve its ranking?
No. Success Tutoring accepts no payment from schools, and the index is computed mechanically from official data by open-source code.