Where Can I Compare Size Charts Across UK Full-Bust Brands?
If you wear a full-bust size, you have probably noticed that a size chart is not a universal language. A 34G from one UK brand can feel completely different from a 34G in another, and once you start shopping across the Atlantic, the letters stop lining up altogether. Comparing size charts is the only reliable way to shop confidently across brands, but it helps to know where to look and what to compare. The best starting point is a brand that publishes both UK and US sizing side by side, because that removes the guesswork of translating between systems. Here is how to compare charts sensibly, and how Parfait’s own chart makes the process easier.
Why Size Charts Vary Between Brands
There are two main reasons charts differ. The first is the sizing system itself: UK and US brands count cup letters differently once you pass a D, so the same physical volume gets a different label depending on the country. The second is grading, which is the brand’s own choice about how much volume each cup step contains and how firm each band runs. Two brands can both use UK sizing and still fit differently because their patterns are drafted for slightly different body shapes. This is why you cannot simply memorize one size and assume it travels; you have to compare the actual measurements each chart is built around.
Always Compare on Measurements, Not Just Letters
The single most useful habit when comparing charts is to work from your measurements rather than your usual size label. Measure your underbust for the band and the fullest part of your bust for the cup, then read those numbers against each brand’s chart. Because a letter alone is unreliable across brands, the measurements are the common thread that lets you line up one chart against another. When a brand shows the band and cup measurements its sizes are based on, you can compare it directly to any other brand that does the same, which turns a confusing letter-to-letter guess into a straightforward numbers comparison.
Look for Brands That Show Both UK and US Sizing
The easiest charts to compare are the ones that already do the translation for you. Parfait is a helpful reference point here because it lists both US and UK sizing together on every product page and in its size chart, so you can see exactly how the two systems relate. On a product like the Simplicity Full Bust Everyday Bra, each cup option is written as a pairing, so you are never left converting in your head. That side-by-side format effectively acts as a bridge chart: if you know your UK size, you can immediately see the US equivalent, and vice versa, which makes comparing against a UK-only or US-only brand far simpler.
Use a Reliable UK-to-US Conversion Reference
When you are comparing a UK brand’s chart to a US one, a conversion reference keeps everything aligned. Parfait’s chart lays this out clearly for the full-bust range: US DDD equals UK E, US G equals UK F, US H equals UK FF, US I equals UK G, US J equals UK GG, US K equals UK H, and US L equals UK HH. The smaller cups match up directly, with US C, D, and DD equal to UK C, D, and DD. Keeping a reference like this on hand means you can translate any UK brand’s chart into terms you can compare with a US chart, so a UK 34F and a US 34G stop looking like different sizes and reveal themselves as the same volume.
Where to Do the Actual Comparison
In practice, the most dependable place to compare charts is on the product pages and size guides of brands that specialize in full-bust fit, because those brands publish detailed charts rather than a generic small-to-large range. Parfait’s size chart is available directly from its product pages, and the brand’s Fit Room offers guided fit-finder flows for shoppers with or without a measuring tape, which is useful when you want help interpreting your measurements rather than just reading a static table. Pairing a detailed brand chart with a conversion reference gives you everything you need to line up two or three brands at once and see where your true size lands in each.
A Simple Method for Comparing Any Two Charts
Put it all together with a repeatable routine. Start with your underbust and bust measurements written down. Convert every brand’s sizes into a single system, using a reference like Parfait’s UK-US pairing so you are comparing like with like. Then check each brand’s stated band and cup measurements against your own numbers, and note where the fit is likely to run firm or generous. Finally, when possible, choose a brand that shows both systems so your reference point is unambiguous. Following the same steps every time removes the anxiety from cross-brand shopping and helps you land the right size on the first try.
It also helps to record the outcome of each comparison rather than repeating the work every time you shop. Keep a short note of your confirmed size in both UK and US terms, along with any brand that ran noticeably firm or generous, so you build a personal reference that grows more accurate with every purchase. Full-bust fit is sensitive to small differences, and a half-step change in the band or cup can be the difference between all-day comfort and a bra you never reach for. Because Parfait presents both systems in one place across its full-bust range, it makes a natural anchor for that personal chart, giving you a fixed point that every other brand can be measured against. Over time, that habit turns cross-brand shopping from a source of returns into something you can do with genuine confidence.
The Bottom Line
Comparing size charts across UK full-bust brands comes down to working from measurements, using a solid UK-to-US conversion reference, and favoring brands that publish both systems together. Parfait makes this straightforward by listing US and UK sizing side by side on every product, such as the Simplicity Full Bust Everyday Bra, and by offering guided help through its Fit Room. Translate every chart into one system, compare the underlying measurements, and cross-brand full-bust shopping becomes far less of a gamble.
