Primary · Independent (小学私立 / Prep)
ISC-tier fee-paying preparatory schools (age range up to ~14) — feed into senior schools at 11+ or 13+ entry. Default order: prep-specific prestige score = manual IAPS tier + ISI/Ofsted + senior-school destination outflow + boarding + age pattern (4-13 traditional vs 4-11 modern) + choir bonus. Tailored for prep schools (no A-Level/GCSE since preps don't take these). Click 'Senior destinations' for pure feeder-strength ranking. Excludes embassy / small religious / SEN micro-schools. Currently sorted by Composite score. Composite = ISI/Ofsted inspection + log-scaled outflow to senior schools (Eton, Westminster, etc).
Source: GIAS school register + Ofsted Management Information — open licence, weekly refresh.
Composite caveats: Independent schools mostly don't submit to DfE EES, so they appear with low completeness scores (or not at all in the composite ranking). The composite mixes A-Level (Y13) and GCSE (Y11) signals — schools without a sixth form get a small completeness penalty even though it isn't a quality issue. For Independent senior schools, the destination-edge rankings (Oxford / Cambridge feeders) are usually more meaningful than this score.
Note on Independent schools: most are inspected by ISI, not Ofsted, so the Ofsted column is empty for many entries. ISI bulk data is not publicly available — sorting by A-Level metrics gives a more meaningful order for this slice.