ONS personal inflation calculator: Measure, Periods & Comparison Checklist

What this reference provides

An official spending-based illustration for understanding why a household's inflation experience can differ from a UK headline rate.

Measure and geography

The tool uses CPIH and asks about household spending categories. Unentered categories can use indicative spending estimates; the detailed workflow allows more explicit inputs.

Period basis

This is a personal-basket illustration around the tool's stated reference period, rather than our U.S. monthly historical conversion. Inspect its current period and expenditure-estimate notice before comparison.

Boundaries

It cannot predict future prices or reproduce every change in shopping choices. Household spending assumptions and a headline national index answer different questions.

A practical comparison task

Run the official tool with two deliberately different spending mixes. Note which categories are estimated and compare those assumptions before comparing the resulting rates.

Keep the interpretation with the result

Keep rent, mortgage and owner-occupier measures distinct when choosing a household comparison. Do not insert an ONS personal rate into a U.S. CPI series and describe the result as a single observed historical index. Our site links to the official tool and does not collect household spending.

Primary source

ONS personal inflation calculator methodology — checked 17 October 2026. This page does not claim an authenticated test or a complete catalogue of the source’s data series.