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Admission age calculator

Work out a child’s completed age as at the admission cut-off date rather than today. Eligibility for a class is always assessed on the cut-off the state publishes for that academic year, which is why a child eligible in one state is not in another.

Cut-off dates and the age band for each class are set by the state and revised. Confirm the current circular before refusing or accepting an admission on age.

Written by Checked by K. ManiLast reviewed

A front office is asked this fifty times in an admission season and answers it with a calendar and mental arithmetic. The error is almost never the subtraction — it is computing age today instead of age on the cut-off, which for a March-born child changes the class they are eligible for.

Computed as at
The cut-off, not today
Output
Completed years, months and days
Common cut-off
31 March or 30 September
Set by
The state, and revised
01

Why the cut-off date is the whole question

A child born on 14 July 2021 is four years old for most of the 2025–26 admission season. Whether they are eligible depends entirely on whether they had completed the required age on the state’s cut-off — and against a 31 March cut-off they had not, while against a 30 September one they had.

This is also why a family moving between states mid-application can find a child eligible in one and not the other, with no error on anybody’s part.

02

What a school should keep on file

The date of birth as it appears on the birth certificate, in figures and in words, and the certificate itself. Age disputes surface years later — at a board registration, or when a transfer certificate is issued — and the school’s position is only as good as the document it recorded at admission.

FAQ

Questions people ask

Phrased the way they arrive, answered so each one stands on its own.

What is the usual admission cut-off date?

31 March is the most common, with 30 September also used. It is set per state and revised, so confirm the current circular rather than relying on last year’s.

Does age eligibility differ by board?

It is primarily set by the state rather than the board, and it varies. A child eligible in one state may not be in the next.

Should we go by the birth certificate or the previous school record?

The birth certificate. Where a previous school’s record disagrees with it, that discrepancy needs resolving at admission rather than at board registration.

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Provenance

Who checked this, and against what

Accountability

Checked by the Implementations desk on 6 September 2026. Corrections go in the page, dated, rather than quietly.

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