How much percentage of salt is present in salt water?

Seawater contains a large amount of dissolved salts, which makes it salty. On average, seawater contains about 3.5% dissolved salts. These salts include sodium chloride (common salt) along with salts of calcium, magnesium, potassium, and sulphates.

Because of this high salt content, seawater is not suitable for drinking unless the salt is removed through desalination processes.