There are two rules which you should consider.
Compare usually takes the preposition to when it refers to. the activity of describing the resemblances
between unlike things:
• He compared her to a summer day.
• Scientists sometimes compare the human brain to a computer.
Compare takes with when it refers to the act of examining two like things in order to discern their
similarities or differences:
• The police compared the forged signature with the original.
• The committee will have to compare the Senate's version of the bill with the version that was passed by the House.
When compare is used to mean “to liken” (one) with another, with is traditionally held to be the correct
preposition: That little bauble is not to be compared with (not to) this enormous jewel. But “to” is
frequently used in this context and is not incorrect.
Rule 1: Compare to compares unlike things, whereas compare with compares like things.
Rule 2: Compare to is used to stress the resemblance. Compare with can be used to show either
similarity or difference but is usually used to stress the difference.
There is a difference between compare to and compare with; the first is to liken one thing to another;
the second is to note the resemblances and differences between two things.
