When the value of the reaction quotient is equal to the value of the equilibrium constant, Q=K, the reaction is at equilibrium.
When the reaction quotient is smaller than the equilibrium constant, Q. When the reaction quotient is larger than the equilibrium constant, Q>K, the reaction is not at equilibrium. The reaction proceeds in backward direction.
When the equilibrium constant is much larger than 1, K>>>1, the reaction is nearer to completion.