The fluid ounce is two units wearing one name, and packaging is where that costs money. A chart that shows both systems next to the metric figure removes the guess from your specification.
The Conversion Chart Your Order Should Quote From
| Metric | US fluid ounces | Imperial fluid ounces |
|---|---|---|
| 100 ml | 3.4 oz | 3.5 oz |
| 200 ml | 6.8 oz | 7.0 oz |
| 250 ml | 8.5 oz | 8.8 oz |
| 330 ml | 11.2 oz | 11.6 oz |
| 355 ml | 12.0 oz | 12.5 oz |
| 375 ml | 12.7 oz | 13.2 oz |
| 473 ml | 16.0 oz | 16.7 oz |
| 500 ml | 16.9 oz | 17.6 oz |
| 750 ml | 25.4 oz | 26.4 oz |
| 1000 ml | 33.8 oz | 35.2 oz |
Why Two Ounces Exist and What It Costs You
A US fluid ounce measures 29.5735 ml and an imperial one measures 28.4131 ml. The gap looks small and compounds with size.
On a small jar it is a few millilitres and on a litre it passes 40 ml, which is enough to move a fill line, a label claim and a customs declaration. Naming the system on your specification costs nothing and removes the whole problem.
Which Trade Sizes Your Order Can Pick From
Some numbers in the chart are conversions and others are established formats. 355 ml, 473 ml and 750 ml exist as sizes in their own right, and 330 ml and 500 ml are the European equivalents.
Tooling already exists for each of them. SGSBOTTLE stocks the common trade sizes across 14 lines in Shandong and Xuzhou, and a custom format outside them needs a mould rather than a stock pick.
Trade sizes come with tooling behind them. SGSBOTTLE runs 14 lines in Shandong and Xuzhou.
Reading the Rounding on Your Specification
The trade rounds in both directions, and the rounding is a label convention rather than a measurement. A bottle sold as 12 oz holds 354.88 ml and is described as 355 ml, and neither number is wrong.
Your specification should carry the exact figure anyway. SGSBOTTLE states brimful and nominal capacity on the drawing for glass from the 14 lines in Shandong and Xuzhou, so your filler works from a measurement rather than from a name.
Why Nominal Is Not What Your Bottle Holds
Every trade size describes the intended fill, not the volume to the brim. Your bottle holds more, because headspace has to exist for the closure, for expansion and for your filling method.
That difference matters on any hot fill or carbonated product. Ask for the brimful figure alongside the nominal one, and set your filler from the drawing rather than from the size on the carton.
What Goes on Your Enquiry
Your target fill in ml and oz, which ounce system your market uses, your product and fill temperature, and your closure. SGSBOTTLE comes back with the stock formats closest to your figure, their brimful capacity and the tolerance on each.