The typical number of lands in a Commander deck usually ranges between 35 and 40 lands. Most average Commander decks tend to run around 36 to 38 lands to ensure consistent land drops throughout the game, especially in three or more color decks

. Some expert analyses and simulations suggest starting with about 40 to 42 lands as a baseline, then adjusting downwards if you include mana rocks or mana dorks (creatures that produce mana), cutting roughly one land for every two or three mana sources added

. This usually results in a final land count around 36 to 38 lands for midrange decks. The total number of mana sources (lands plus mana rocks and other mana-producing cards) often falls between 43 and 55, with the land base itself typically between 33 and 40 lands depending on the deck's curve and ramp options

. In summary:

• Average Commander decks: 35-38 lands
• Starting baseline for midrange decks: ~40-42 lands, adjusted down with mana rocks/dorks
• Total mana sources (lands + rocks): ~43-55
• Lower land counts possible in decks with lots of ramp or cheap spells; higher counts for decks with big spells or land-focused strategies

Therefore, a good rule of thumb is to include about 36-40 lands in a Commander deck, adjusting based on your deck’s ramp and mana curve.