I don't want to go into a shop to get measured by someone. I have tried using the figleaves size guide but I can't find the bit where it tells you how to do it.
I am 30.5 inches underbust and 37.5 inches over the bust. Can anyone advise me. My current bras are 34c, d and e. I know I should go and try some on but I also wanted to be able to order on the internet.
I don't think it can be 30 g? They aren't that big, honest. I came out as a 36b on this but that is definitely wrong. If I take off the half inch under the bust I come out as 34d which might be okay. But I was thinking of buying a lower band size as the ones I'm getting are stretching out too quickly and becoming a bit useless.
30 or 32 depending on the brand, definitely not 36. And online bra calculators are horrible. You know that a new bra should fit when fastened on the loosest hook, right? So you can tighten them when they stretch and they won't become useless so quickly.
And about not being big enough for a G? Well, as you say you have 34E bras - which is the same cup size as 30G. If you go down a band size you need to go up a cup to get the same volume. So 30G is the same as 32F or 34E or 36DD.
A good bra fitter will look, ask what size you're wearing and work it out from there. They will also know what shapes and styles should work on your shape. All brands are slightly different and there's no substitute to trying on. I only buy online where I already have bras of that shape and brand.
John Lewis are pretty good, plus bravissimo and independent places. Don't go to M&S as they are renowned for being rubbish at fittings.
The back strap should be low on your back, not riding up, and the wires should touch between your boobs. Once you've had a proper fitting you'll feel more confident in knowing what's right on you.