Aspects of a method and system for frequency tuning based on characterization of an oscillator are provided. A value of a first control word which controls a variable impedance of an oscillator may be determined. The determined value may be mapped to a corresponding value of a second control word which controls a variable impedance of a tuned circuit. The mapping may be based on a relationship between the variable impedance of the oscillator and the variable impedance of the tuned circuit, such as logical and/or mathematical relationship. The value of the first control word may be determined based on desired frequency of the tuned circuit and/or based on a desired impedance of the variable impedance of the tuned circuit. The tuned circuit may comprise, for example, an oscillator or a filter.