Card Draw Probability Calculator
Find the exact odds of drawing the cards you need from a deck (at least one copy, exactly so many, or none) using the hypergeometric distribution. Calculates in your browser.
P(at least target)
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Show the math
Drawing without replacement follows the hypergeometric distribution, the exact odds of pulling k of your target cards in an opening hand:
P(k) = C(K,k)·C(N−K, n−k) / C(N,n)
Great for deck-building: how often you'll see a key card, a combo piece, or land/mana early.
All math runs locally in your browser.
What this does
A card draw probability calculator finds the exact odds of drawing the cards you need — at least one copy, exactly so many, or none — using the hypergeometric distribution.
How to use it
- Enter the deck size.
- Enter the number of target cards.
- Enter how many you draw.
- Read the odds.
How it works
The hypergeometric distribution gives exact odds for drawing without replacement from a deck of known size — ideal for deck-building math.
Understanding your result
These are exact hypergeometric odds for drawing without replacement, which is the right model for a deck, unlike dice, the cards you have already drawn change what remains. Use the at-least-one figure to tune how many copies of a key card you need: the odds of seeing it in your opening hand rise sharply with each extra copy, then flatten.
Example
In a 40-card deck with 17 lands, an opening 7 usually holds 2–3 lands.
Sources & methodology
Last updated .
Frequently asked questions
What is the hypergeometric distribution?
It gives the exact odds of drawing a number of target cards when you draw without replacement from a deck of a known size.
What is this useful for?
Deck-building, how often you will see a key card, a combo piece, or your lands and mana in an opening hand.
Is my data kept?
No. Everything is computed locally in your browser.
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