ThirdLove vs Cuup
Two brands, two ways of grading a size. Here is how ThirdLove and Cuup differ in system, range and fit, and which one to choose for your shape and your problem.
ThirdLove or Cuup, in short
ThirdLove and Cuup both label in US sizing. ThirdLove runs true to size in the band and grades generous in the cup with average wires; Cuup runs true to size in the band, true in the cup, narrow wires. Range: ThirdLove 30–48 / AA–H; Cuup 30–44 / A–H. Convert your measured size into each and let fit decide.
Your measured size in both
Same body, two labels. Each result is your US size converted into the brand's system, then adjusted for how that brand grades. Same system, so the label matches: the fit adjustment is the difference.
ThirdLove vs Cuup at a glance
| ThirdLove | Cuup | |
|---|---|---|
| Sizing system | United States | United States |
| Bands | 30–48 | 30–44 |
| Cups | AA–H (I in select bands), plus half-cup sizes A½–E½ on 30–40 bands | A–H |
| Band grading | true to size | true to size |
| Cup grading | grades generous | true |
| Wire width | average | narrow |
| Straps | Standard, adjustable front | Slim, adjustable |
| Alpha sizes | No | No |
| Tier | Mid-to-premium | Mid-to-premium |
| Origin | US | US |
| Signature line | 24/7 Classic T-Shirt: memory-foam contour, the flagship, in half cups | The Balconette: open-top unlined mesh |
Which to try for your breast shape
| Shape | ThirdLove | Cuup |
|---|---|---|
| Full on bottom | 24/7 Classic Demi | The Balconette |
| Full on top | 24/7 Classic Full Coverage | The Scoop |
| Shallow | 24/7 Classic Wireless | The Demi |
| Projected | 24/7 Classic T-Shirt in a half cup up | The Plunge |
| Wide-set | 24/7 Plunge | The Plunge |
Not sure of your shape? Use the shape finder.
Choose ThirdLove or Cuup?
- cups usually feel small on you elsewhere
- between two cup sizes
- memory-foam contour without gaping
- you have a narrow root or projected shape
- unlined bras in a full range
- minimal aesthetic
Both are right at the same measurement. The label differs by system and the fit by grading: start from your measured size, convert into each, and let the five fit checks decide.
What each brand is known for
| ThirdLove | Cuup | |
|---|---|---|
| Line 1 | 24/7 Classic T-Shirt: memory-foam contour, the flagship, in half cups | The Balconette: open-top unlined mesh |
| Line 2 | 24/7 Classic Wireless: wireless contour | The Plunge: deep unlined plunge |
| Line 3 | Classic Strapless (runs tight in the band) size the band up | The Scoop: full-coverage unlined |
| Line 4 | Sport: bra-sized sport | The Demi: light coverage |
ThirdLove vs Cuup: answered
Is ThirdLove the same size as Cuup?
Same notation (US), different grading. ThirdLove: Bands run true to size: start with your measured band on the loosest hook. Cuup: Bands run true to size: start with your measured band on the loosest hook.
Which runs smaller, ThirdLove or Cuup?
ThirdLove (Cups grade generous) try your measured cup and one down. Cuup. Cups grade true to the measured difference.
Which is better for a large bust, ThirdLove or Cuup?
ThirdLove runs to AA–H on bands 30–48; Cuup to A–H on 30–44. The one whose range covers your size (in its own system) and whose wire width suits your root.
Which is better for a small bust?
Whichever grades true or small at A–C: ThirdLove cups grades generous, Cuup cups true. Small bands need the brand whose range starts lower: 30 vs 30.
Can I use my ThirdLove size at Cuup?
Convert first (same system, so the label carries), then adjust: Cuup bands run true to size and cups true relative to true. The calculator above does both.
Do ThirdLove and Cuup fit the same breast shapes?
Not identically. Full on bottom: ThirdLove 24/7 Classic Demi vs Cuup The Balconette; Full on top: ThirdLove 24/7 Classic Full Coverage vs Cuup The Scoop; Shallow: ThirdLove 24/7 Classic Wireless vs Cuup The Demi.
Opens HauteFlair’s own hub page; use your measured size there. HauteFlair is owned by the same company as Brasize.ai; that relationship never changes the sizing math, charts, or fit advice on this page. How this site makes money.