US to AU conversion

30A in Australian Bra Size

Convert 30A from US sizing to Australian sizing, with the full international table, nearby sister sizes, and fit checks in one place.

Instant answer

30A (US) =

8A AU

In this sizing table, 30A in US sizing converts to 8A in Australian sizing.

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If you are starting from body measurements instead of a known label, use the AU/NZ calculator with centimetres selected by default.

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Sizing varies by brand

A conversion gives you the closest label in another sizing system, but brands can grade cups, wires, and bands differently. Use the converted size as a starting point, then check the retailer's chart and the fit of the actual bra.

Before you buy in Australian sizing

Use 8A as the translated label, not as a fit guarantee.
Check the retailer's size chart because some brands grade bands and cups differently.
If the cup volume feels close but the band changes, compare sister sizes before switching cup letters.
When possible, check return rules before buying across sizing systems.

Full conversion table for 30A

30A bra size conversion across US, UK, EU, French, and Australian sizing.
US	UK	EU	FR	AU
30A	30A	65A	80A	8A

Bra sizing varies between brands. Use this as an accurate starting point and check the fit.

Sizes near 30A in Australian sizing

If 30A is close but not right, these are the neighbouring US sizes and what each one becomes in Australian sizing. Band neighbours change the fit around the ribcage; cup neighbours change volume.

US sizes adjacent to 30A and their Australian equivalents.
US size	AU size	How it differs
32A	10A	One band step looser, same cup letter.
30B	8B	One cup step up, same band.

What this conversion means

For 30A, the band stays tied to the 30 US band while the label is translated into Australian sizing. In this dataset, 30A (US) converts to 8A (AU). Treat that as the starting label, then check the brand chart and the real fit.

Sister sizes for 30A

Sister sizes: No in-range sister sizes are available for this edge size. Try the sister size finder for the nearest supported options.

What measurements make a 30A?

30A starts with the underbust, then adds cup depth from the bust measurement. In the current calculator formula, the closest starting range is about 29-31 inches (74-79 cm) under the bust and about 30.5-31.5 inches (77-80 cm) around the fullest part of the bust. The band comes from the underbust rounding, while the cup step comes from the difference between bust and band.

Is 30A big or small?

The label 30A can look more dramatic than it fits, especially across systems. In this size set, the US equivalent uses a smaller band and a lower cup step. Cup letters are relative to the band, so a D on one band is not the same volume as a D on every other band. The most useful question is whether the band stays level and the cups hold smoothly, not whether the label sounds large or small.

If 30A doesn't fit right

Band rides up: The band may be too loose or stretched out; try a snugger band or compare the snugger sister size.

Cups gape: The cup may be too roomy, too deep, or pulled away by a loose band; check the band before changing cup volume.

Cups spill: The cup volume may be too small or the cup shape may be too closed; try one cup step up before changing the band.

Straps dig in: The straps may be compensating for a band that is not supporting enough; reset the band fit before tightening straps.

How 30A differs between brands

Brand sizing matters for 30A because cup depth, wire width, and band stretch are design choices. A firmer elastic can make the same band feel smaller, and a shallow or narrow cup can make the same cup letter feel different. Check the retailer chart, read fit notes when available, and compare the label against the brand and region sizing guide before treating the conversion as final.

Shopping for 30A

A good shopping path for 30A starts with everyday support, then moves into outfit-specific shapes. If the cup is in a lower or middle step, lightly lined T-shirt styles can make gaps easy to spot. Fuller cup steps often benefit from styles with steadier side support, deeper cups, or a balconette shape depending on breast shape. For special outfits, compare the fit needs in the outfit guides before choosing a strapless, plunge, or backless option.

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Soft Cup Edit

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FAQ

Is 30A in the US the same as Australian sizing?

Not exactly. 30A is the US label, and this table converts it to 8A in Australian sizing, though some brands publish their own charts.

What is 30A in UK sizing?

In this same table, 30A converts to 30A (UK). That helps when a retailer shows a UK chart instead of a Australian one.

How do I know if 30A fits?

Check that the band stays level, the cups do not spill or gap, and the center gore sits close if the bra has wires. If the cup feels right but the band feels wrong, try a sister size.

What sister sizes work with 30A?

No in-range sister sizes are available for 30A in this dataset. If the band or cup feels off, recheck your measurements and compare the nearest supported sizes.

Why do bra sizes differ between countries?

Countries and brands do not all use the same band labels or cup-letter sequence. A conversion translates the closest standard label, but the final fit still depends on the specific bra.

What measurements usually make 30A?

The current calculator formula points to about 29-31 inches underbust and 30.5-31.5 inches bust, or roughly 74-79 cm and 77-80 cm. Treat that as a starting range and then check the real fit.