Compared to vs. compared with

Maybe this helps.

Compared To: When you want to show similarity between two unlike things.
Compare to is used to stress the resemblance.

• He compared her to a summer day. (two unlike things- ‘her’ and ’summer day’ )
• Scientists sometimes compare the human brain to a computer. (two unlike things- ‘human brain’ and ‘computer’.

Compared with : When you want to show similarities or differences between two like things.
Compare with can be used to show either similarity or difference but is usually used to stress the difference.

• The police compared the forged signature with the original. (two like things- two signatures)
• The committee will have to compare the Senate’s version of the bill with the version that was passed by the House. (comparison between two like things- two bills)

The traditional rule about which preposition to use after compare states that compare should be followed by to when it points out likenesses or similarities between two apparently dissimilar persons or things: She compared his handwriting to knotted string.