1000 ml makes a litre. ml, also written as mL stands for millilitres. It is one of the commonest standards of measurement in the metric system, along with the litre. One millilitre is only one-thousandth of a litre or a cubic centimetre.
In the Imperial measurement system, a millilitre equates to only 0.00026 of a gallon, 0.002 of a pint, 0.001 of a quart, and 0.004 of a cup. When going for your shopping or measuring for cooking, remember that the metric measurement system is quite different from the Imperial system.
While the Imperial measurement system calculates size differences by volume, the metric system measures by weight. This difference often makes conversion tricky. However, the metric system reminds the most popular and accepted measurements. Apart from the United States, Liberia, and Myanmar, all other countries use the metric system.
So, it is safe to convert your one litre to 1000 millilitres, following the metric system as long as you are not in any of these three countries.