After running a game report, and looking at the analysis tab, you may have noticed a number describing the 'depth' in the upper right corner:

This number describes how many moves ahead the engine is looking in order to make its decision on what the best move is, what is a blunder, and so on. The higher this number, the more sure you can be about how accurate the engines decisions are.

Note: this number can be higher when the engine is analyzing a 'book move' because the engine already has loads of data on the opening moves, and is able to look much farther ahead.

You can adjust the depth by clicking the setting gear icon to the right of the depth:

Game Review and Cloud Analysis can be adjusted only by Diamond members. Browser Analysis can be adjusted by all members.

The game review and positional analysis are calculated in the 'cloud' meaning the analysis is done using Chess.com's servers. This means the analysis is much quicker and stronger.

When you are doing self analysis (playing out your own moves, separate from the game report, in the analysis tab' then the analysis is done by your own computer or device (browser analysis) and so is a bit slower.

If you click on the dropdowns you can adjust the depth or 'moves ahead' you want the analysis to look:

If you choose unlimited, your computer or device will keep looking ahead indefinitely! After a few minutes though it will take a very long time for the next move deep, since it gets exponentially harder to look each move deeper.