Where our data comes from — and what it can and can't tell you
ofsted.london aggregates official, publicly available data about London schools into a single, searchable resource. We are an independent site: we are not affiliated with Ofsted, the Department for Education (DfE) or any local authority, and no school pays to appear here or to influence how it is presented. This page explains exactly where every number on the site comes from, how often it is refreshed, and — just as importantly — where the data has limits.
Primary data sources
How we process the data
Each source is downloaded from its official publisher, filtered to schools located in the 33 London local authority areas (the 32 boroughs plus the City of London), and joined on the school's unique reference number (URN). The combined dataset covers around 3,200 schools. We do not alter any published figure: attainment percentages, progress scores and inspection outcomes appear exactly as released. Where the DfE suppresses a figure — typically because a cohort is too small for reliable reporting — we show a dash rather than estimating a value.
Rankings on our "best schools" pages are ordered by published KS2 attainment or Ofsted outcome, with ties broken alphabetically. A ranking based on attainment reflects the intake of a school as well as the quality of its teaching, which is why every ranked list on the site links to progress scores and FSM context — a school in a highly disadvantaged area achieving average results may be doing a more impressive job than a school in an affluent area achieving high ones. Our Beating the Odds tool exists precisely to surface those schools.
Known limitations
Inspection outcomes age at different rates. Some schools were last inspected many years ago; an outstanding judgement from 2015 tells you less than a good judgement from last term. We publish the inspection date next to every outcome so you can weigh it yourself.
Ofsted no longer issues single-word overall judgements. Since September 2024, inspections of state schools have not produced an overall effectiveness grade, and Ofsted has since moved to a report-card model. Schools not yet inspected under the newer arrangements are shown with their most recent judgement from the previous framework, clearly dated.
Most private schools are not inspected by Ofsted at all. Independent schools belonging to the Independent Schools Council associations are inspected by the Independent Schools Inspectorate (ISI) instead. Where a private school shows no Ofsted rating on this site, that is usually why — see our explainer on how private schools are inspected.
KS2 data is a one-year snapshot. Results for a single cohort of a one-form-entry primary school reflect around 30 children; a couple of pupils can move the percentage noticeably. Treat small differences between schools as noise, not signal.
House price and crime figures are area context, not school attributes. They describe the area around a school, and should never be read as a judgement on the school itself.
Corrections
If you represent a school and believe any figure shown is out of date or incorrect, contact us via the details on our about page with the school's URN and the official source for the correction. We verify against the publishing body and update at the next refresh.