In the Klondike solitaire game that comes with all versions of Microsoft Windows (known as "Windows Solitaire"), using Standard Scoring, the highest possible score is 24113.
Standard Scoring in the Windows Solitaire game is accomplished as follows:
You receive 5 points per card brought from the deck to the table and 10 points per card brought from the table to the foundation at the top.
Bonus points are calculated with the formula of 700,000 / (seconds to finish) if the game takes more than 30 seconds. If the game takes less than 30 seconds, no bonus point is awarded.
See also: International Solitaire Rankings.