Apparel SizeShoe Size

BR to AU Shoe Size for Kids

Snapshot

30 BR size equals 5.5 AU size. Conversion Encyclopedia uses the same fixed conversion basis across the calculator, common values, and reverse page for this page.

Reference basis: This result uses the selected selected cohort cohort as the profile basis.
Example: For 27 BR size, the selected cohort cohort returns 3 AU size under the same mapping assumptions.
Use the reverse page if you need the opposite direction with the same basis.

Use the interactive calculator below for custom values and the common-value table for quick checks.

Interactive conversion

Converter Calculator

5.5 AU size

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Machine access

Available to apps and AI agents

BR to AU Shoe Size for Kids can be requested through Conversion Encyclopedia's structured interfaces by software and compatible AI agents. The kids cohort identifies the sizing system used by the conversion.

Machine-readable identifiers

Conversion family: shoe-size
Source unit: br
Target unit: au
Cohort: kids

The JSON API and OpenAPI specification use the identifiers to reach the conversion engine. WebMCP lets compatible AI agents request the same calculation.

Example API request and response

POST /api/v1/convert

Request

{
  "family": "shoe-size",
  "value": 30,
  "from": "br",
  "to": "au",
  "parameters": {
    "cohort": "kids"
  }
}

Essential response

{
  "ok": true,
  "conversion": {
    "family": "shoe-size",
    "value": 30,
    "from": "br",
    "to": "au",
    "result": {
      "raw": 5.29921349216,
      "display": "5.5"
    },
    "canonicalPath": "/apparel-size/shoe-size/br-to-au-for-kids/"
  }
}

Full API documentation

Explanation

BR converts to AU by first mapping BR to millimeters, then mapping millimeters to AU. Cohort profile fixed: Kids.

From BR size to AU size, results depend on the selected selected cohort cohort and stay consistent with that cohort across table rows and calculator input.

Keep the same cohort in both directions to avoid mixing shoe-size systems that use different wearer-group mappings.

Method & Size Mapping

Model basis: output depends on the selected shoe-size cohort and follows the same cohort mapping in both directions.
Profile reference: selected cohort cohort.
Consistency rule: calculator output and table values keep the same shoe-size cohort in both directions.

Common Conversion Values

BR size	AU size
27	3
29	4.5
30	5.5
32	7
33	7.5

Questions & answers

Frequently Asked Questions

Is the reverse shoe-size direction available?

Yes. The mirror page AU to BR (Kids) uses the inverse mapping path.

Which shoe-size cohort is used for BR to AU?

Kids sizing is fixed for this shoe-size mapping.

What formula is used for BR size to AU size?

The converter applies the formula defined for BR size to AU size, then renders rounded output for the direct answer and common-value rows.