Do I need to dilute paint for an airless sprayer?

Do you need to dilute paint for an airless sprayer depends on paint type, sprayer power, tip size, and manufacturer recommendations, but generally most modern airless sprayers, especially Graco Magnum and professional models, can spray latex and oil-based paints without dilution, while some thinner or weaker sprayers may require slight thinning. High-quality airless sprayers with at least 1500 to 3000 PSI and large tips like 0.015 to 0.021 inch can spray unthinned latex paint directly from bucket, which is a major advantage of airless over HVLP that often requires thinning. However, if paint is very thick, cold, or old, or sprayer is low-powered handheld, you may need to thin 5 to 10 percent with water for latex or mineral spirits for oil-based to improve flow and atomization and prevent clogging. Always check paint can label, many say airless spray ready or do not thin, while some say thin up to 10 percent if needed. For primers and thick elastomeric coatings, thinning may be recommended. To test, try spraying unthinned first on cardboard, if you get tails or poor atomization, thin slightly. Over-thinning reduces coverage and causes runs. So for most homeowner airless like Graco X5, you do not need to dilute latex, but you can thin 5 to 10 percent if needed for smoother finish, especially in cold weather.