Knit fabrics are measured according to weight.
Woven fabrics are measured according to area.
To make this easier consider this…
1 yard does not equal 1 meter, so you can’t directly convert them. To get the proper conversion you need to take into account that 1 meter equals 1.09 yards.
Here is how to convert oz/yard2 to g/m2
1oz/yard2 = 33.9g/m2
1g/m2 = 1oz/yard2 / 33.9
33.9 x oz = gsm weight (grams per square meter)