Today’s Classic column, http://www.straightdope.com/columns/read/2289/whats-the-largest-commercially-available-bra-size, is from 1976. Any comment on whether the numbers are still accurate. I ask this question for a totally scientific reason, to see if the general fattening of America has led to an increase in all bodily areas, or something like that. 
Here is a strapless bra available in 50L.
I was wondering about an update to that column as well. After all, nanotechnology/3-D printing/JIT logistics/mass customization/something must have led to advances in the field… 
My understanding (I’m more a butt man myself), is that the NUMBER refers to your chest size, and the LETTER refers to your cup size. So a 50A is still flat chested.
And cracked.com (the internets second best educational site) tells us that JJ is a retail-available cup size: 5 nightmare realities having absurdly large boobs.html. As it explains “#3. Clothes Are Science-Fiction Nightmares”
And here I thought it was the Zebra.
Thank you I’ll be here all week. Tip your server.
This site offers some up to N cup (in surprisingly small band sizes…those would be for the nursing mom, surgically enhanced to fetish zone or an actual medical condition called macromastia or gigantomastia.) http://www.biggerbras.com/catalog-favorites/bras-bgb-favorites.shtml
British cup sizes are different from American; British manufacturers tend to double up each letter code (D, DD, E, EE, F, FF, etc.), so an L would (theoretically) be an American Q. Which is absolutely insane, so I must be wrong here somewhere.
Powers &8^]
Riiighht. Where to start.
First off, I’ll use UK sizing, for the simple reason that bra sizes commercially available here (and in Australia, but their only sizing difference is that the numbers are halved) get far bigger than in the US, for some reason, so US websites will sometimes just switch to UK sizing once they hit the big time, and anyway, the biggest bra will not be sold in US sizing.
It’s not as simple as doubling all the letters, the sequence goes:
AAA, AA, A, B, C, D, DD, E (no EE), F, FF, G, GG, H, HH, (no I) J… then simply double.
As a few people have said, the letter represents the cup size, the number is the band size, but (of course!) it isn’t as simple as that. D is not just D. Take a 34DD bra; if you could remove the cups and reattach them to a 30 waistband, the cup size would jump up to an F; likewise, if you attached them to a 36, they’d shrink back to a C.
You drop two inches from the number, you step up one on the letter. Thee same basic principle, so far as I can find out, applies to all the different country sizing systems.
There’s some minor reshaping between sizes, but the underwire and cup volume on a 28GG (GG, that’s massive, right!?) would be the same size as the cup on a 48A (A? That’s tiny!).
In order to find the largest commercial size, that means you have to find the largest number/letter combo, not simply either one.
Cecil was obviously hypnotised by boobs into skimping the research on this one.
-Filbert, who’s spent far too much time in specialist bra shops.
I was quite shocked to find out that I need a DD bra. I always thought that was considered “big busted”, and I could best be described as “regular sized”.
Most women do not know their actual bra size; they often use the same size they had when they were about 12, and never get remeasured.