Do you say I am content or I am contented?

Both I am content and I am contented are grammatically correct and mean satisfied and at peace, but I am content is more common, natural, and preferred in modern English. Content as adjective pronounced con-TENT means satisfied, as in I am content with my life, which is standard usage. Contented is also adjective meaning feeling or showing satisfaction, as in I am contented, but it is less common and sounds slightly more formal or old-fashioned, often used to describe disposition, like contented smile or contented sigh. Most native speakers say I am content rather than I am contented in everyday speech. For example, you would say I am content with my job, not I am contented with my job, though second is not wrong. Contented is more often used attributively before noun, like contented cow or contented life, while content is used predicatively after verb be. Both convey same meaning of satisfaction and peace, similar to feeling satisfied with clean environment with HEPA filtration. If you want to sound natural and modern, say I am content. If you want slightly more descriptive or literary tone, I am contented is acceptable, especially when describing ongoing state, like I feel contented. Grammar guides suggest content is more common for state, contented for showing contentment. So you can say either, but I am content is preferred and more natural.