Short answer: capacity (oz or ml) tells you how much the cup holds, but the rim diameter in millimetres decides which lid fits. Choose one or two rim diameters — most often 90 mm, 95 mm or 98 mm — and build your size range around them.
Ounces to millilitres
| Size | Nominal ml | Common rim | Typical drink |
|---|---|---|---|
| 9 oz | 270 ml | 78 mm | Water, juice, sampling |
| 12 oz | 360 ml | 90–98 mm | Small iced coffee |
| 16 oz | 500 ml | 90–98 mm | Standard iced drink, bubble tea |
| 20 oz | 600 ml | 90–98 mm | Large iced drink |
| 24 oz | 700–790 ml | 90 / 98 / 117 mm | Fruit tea, smoothies |
| 32 oz | 1000 ml | 117 mm | Jumbo drinks, fruit cups |
Note that "16 oz" can be 450 ml to 500 ml depending on the mould. Always confirm brim-full capacity versus fill-line capacity with your supplier.
Why rim diameter matters more than capacity
Lids snap onto the rim, and sealing machines are set to a specific diameter. If you keep 12, 16 and 20 oz cups on the same 90 mm or 98 mm rim, one flat lid and one dome lid cover your whole range, and one sealing-machine mould fits everything.
Popular rim families
- 78 mm — small cold cups and tasting cups.
- 90 mm — the Asian bubble-tea standard for PP injection cups.
- 95 mm / 96 mm — common for PET cold cups in Europe and the Middle East.
- 98 mm — the North American standard for PET and PLA cold cups.
- 107 / 117 mm — wide deli cups, 24–32 oz drinks and fruit cups.
Checklist before ordering
- Measure your current lid or sealing-machine mould.
- Confirm brim-full and fill-line capacity.
- Decide wall thickness by drink type — thicker walls for shaken or heavily iced drinks.
- Ask for a sample set of cups and lids to test together.
Frequently asked questions
Is 16 oz always 500 ml?
No. 16 oz is about 473 ml in US fluid ounces; many Asian moulds call a 500 ml cup '16 oz'. Check the brim-full capacity.
Which rim size is best for bubble tea?
90 mm is the most common for PP injection cups and sealing machines in the bubble-tea industry.
