Oil and gas ratio charts for two-stroke engines provide the amount of each component to mix together for proper use. A ratio chart shows a ratio of gas to oil, such as 50:1, then lists the appropriate volumes of each below.
A two-stroke, or two-cycle engine differs from a traditional engine in that oil and gas are premixed in a specific ratio prior to being added to the engine. Two-cycle engines are often used in smaller gas-powered items such as lawnmowers, snowblowers, or pressure washers. Each engine is designed to use a specific ratio of gas to oil, so consult your item's user manual for the ratio and appropriate amounts.
Use only oil labeled for use in two-stroke or two-cycle engines, which is available at most automotive supply stores or major retailers. To mix the gas and oil, first add the required amount of oil to a gas can, then slowly add the gas. Do not attempt to try to mix the gas and oil directly in the gas tank of the engine; it must be premixed then added. It is best to use a fresh mix of gas and oil, and mixtures over 30 days old should not be used.