Weight (Mass):
1 kilogram (kg) = 1,000 grams (g)
Capacity:
1 litre (L) = 1,000 millilitres (mL)
Both use the same conversion factor: x 1,000 for the larger-to-smaller direction.
In Indian context: a bag of sugar = 1 kg = 1,000 g. A large water bottle = 1 L = 1,000 mL.