Is it oil or latex paint?

Is it oil or latex paint?

When you’re not sure if the surface you are re-painting has oil-based or latex paint on it, dab a cotton ball or cotton swab in rubbing alcohol and lightly rub the cotton over the surface to be painted for a few seconds.  If a paint film comes off on the cotton, the paint is latex.  If the cotton is clean, the paint is oil-based.

Oil-or-Latex