Unlike most versions of Klondike, Solitaire City features a timed scoring system. The faster you complete the game, the higher your score. Here's how the scoring works:

Good Points

Turning over a face down tableau card+25 Points
(max = 525)
Playing a card from stock to tableau+45 Points
(max = 1080)
Transferring a card to the foundations+60 Points
(max = 3120)

Bad Points

Every second of elapsed time-1 Point 
Every time Undo is used-25 Points
Exposed card of a packed column to another packed column-25 Points
Moving a foundation card back to the tableau-75 Points
Each re-deal after the third pass through the stock (Deal 3)-125 Points
Each re-deal after the first pass through the stock (Deal 1)-200 Points
Each re-deal after the first pass through the stock (Unlimited Passes)-175 Points

Completion Bonus

When the game is completed, you will receive a bonus calculated in the following way:

Bonus = (2 x End of Game Score) - (10 x Time Taken)

If we ignore the fact that your score is being eaten away each second, if each card in the stock is transferred to the tableau before being transferred to the foundations, the maximum end of game score possible would be 4,725. Therefore the largest possible bonus would be 9,450, making a theoretical highest possible score of 14,175. Obviously this score isn't possible as you would have to complete the game in less than 1 second.

Scores over 10,000 are creditable.
Scores over 11,000 are ones to be proud of.
Scores over 12,000 are monsters !
Scores over 13,000 are SUPERHUMAN !!