2/3 tablespoons of cornstarch in grams

2/3 tablespoons of cornstarch ≈ 5 grams

That is about 0.18 ounces. Also sold as cornflour. One US cup of cornstarch weighs 120 g.

tablespoons

grams

Why this number is approximate

Note the naming trap: "cornflour" means cornstarch in the UK and finely ground cornmeal in the US.

Cornstarch conversion table

Cups	Grams	Ounces	Tablespoons
1/4	30 g	1.06 oz	4
1/3	40 g	1.41 oz	5.33
1/2	60 g	2.12 oz	8
2/3	80 g	2.82 oz	10.7
3/4	90 g	3.17 oz	12
1	120 g	4.23 oz	16
1 1/2	180 g	6.35 oz	24
2	240 g	8.47 oz	32
2 1/2	300 g	10.6 oz	40
3	360 g	12.7 oz	48
4	480 g	16.9 oz	64

Weigh it if you can

Volume measures are convenient but imprecise — the same cup can hold noticeably different amounts depending on how the ingredient is packed, how humid the room is, and whether it was sifted. A digital kitchen scale removes the variable entirely, which is why professional and European recipes give weights. If you bake regularly, a scale is the cheapest accuracy upgrade available.

Frequently asked questions

How many grams is 2/3 tablespoons of cornstarch?

About 5 grams, or 0.18 ounces.

How many grams in a cup of cornstarch?

Roughly 120 grams per US cup.

Is a US cup the same as a metric cup?

No. A US customary cup is 236.6 ml; a metric cup — used in Australia, New Zealand and much of Europe — is 250 ml, about 6% larger. An imperial cup, still seen in older British recipes, is 284 ml. For a cup of cornstarch that is a difference of roughly 6.8 g between US and metric.

Should I sift before or after measuring?

It matters, and recipes are often ambiguous. "1 cup sifted flour" means sift first, then measure — which gives less flour than "1 cup flour, sifted", where you measure first. When in doubt, weigh.

Other amounts

All cornstarch conversions · All cooking conversions