Methanol is completely soluble in water, and it is the most soluble of any alcohol. Methanol is the smallest alcohol in terms of number of atoms, with a chemical formula of CH3OH.
Alcohols are a type of chemical group that consist of a carbon chain and a hydroxide group, OH, on the end. Water readily dissolves polar molecules, which means it interacts highly with the hydroxide group. Since methanol is such a short molecule, water has no trouble dissolving it. As alcohols get longer, the hydroxide group becomes a proportionally smaller part of each molecule. This is why alcohols become less soluble until they become immiscible, as the carbon chain is not a polar component.