On a hard 16, the chance of busting on your next card is 61.54% in the infinite-deck model. On a soft 16, it is 0%: the ace can switch from 11 to 1. The calculator below shows this one-card risk and how it changes when you account for known cards in a finite deck.
Calculate your next-card bust risk
See the chance of going over 21, staying in the hand, and reaching 21 on one hit.
· one additional card
“Reach exactly 21” is included in “Stay at 21 or below”; these are not three separate outcomes.
Show the result for every possible next card
| Next card | Chance | Resulting hand |
|---|
J, Q and K each count as 10 points. A row with a 0.00% chance is unavailable in the remaining card pool.
This is the risk of busting on one hit, not the probability of losing the round or a hit/stand recommendation.
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How to use the calculator
Choose Quick estimate to select a hard or soft hand and its total. This mode treats each rank as equally likely on every draw, without removing any previously dealt cards.
Choose Known cards to start with 1, 2, 6 or 8 standard decks. Enter your actual hand, then optionally add the dealer’s visible card and other exposed or discarded cards from the same shoe. Each listed card is removed once. Keep J, Q and K separate from 10 when entering cards, because the calculator checks the available count of each rank.
The results show:
- Bust on next card: the probability that one additional card puts your hand over 21.
- Stay at 21 or below: the complementary probability. This does not mean you win the round.
- Reach exactly 21: a subset of the non-bust outcomes, not an additional outcome to add to them.
Open the next-card breakdown to see the probability and resulting hand for every rank. The tool measures one hit; it does not simulate a sequence of hits or recommend an action.
Blackjack bust probability chart
This chart assumes an infinite deck. Each rank has probability 1/13, so 10, J, Q and K together account for 4/13 of possible next cards. The percentages are rounded to two decimal places.
| Current hand | Cards that cause a bust | Bust probability |
|---|---|---|
| Hard 11 or less | None | 0% |
| Hard 12 | 10, J, Q, K | 4/13 = 30.77% |
| Hard 13 | 9, 10, J, Q, K | 5/13 = 38.46% |
| Hard 14 | 8, 9, 10, J, Q, K | 6/13 = 46.15% |
| Hard 15 | 7, 8, 9, 10, J, Q, K | 7/13 = 53.85% |
| Hard 16 | 6, 7, 8, 9, 10, J, Q, K | 8/13 = 61.54% |
| Hard 17 | 5, 6, 7, 8, 9, 10, J, Q, K | 9/13 = 69.23% |
| Hard 18 | 4, 5, 6, 7, 8, 9, 10, J, Q, K | 10/13 = 76.92% |
| Hard 19 | 3, 4, 5, 6, 7, 8, 9, 10, J, Q, K | 11/13 = 84.62% |
| Hard 20 | 2–10, J, Q, K | 12/13 = 92.31% |
| Any soft hand, 12–21 | None on the next card | 0% |
A 0% bust probability is not a reason to hit every soft hand. It only describes what can happen on the next card. A hand already totaling 21 is complete.
How the probability is calculated
P(bust on one hit) = number of cards that would bust the hand ÷ number of possible next cards.
For an infinite-deck hard total t from 12 through 20, this simplifies to (t − 8) / 13. For example, hard 14 busts on 8, 9 and the four ten-value ranks: six ranks out of thirteen, or 46.15%.
For a finite deck, the calculator counts the cards remaining after the known removals. It evaluates every possible next rank, adjusts any usable ace, and adds the probabilities of totals above 21. No random simulation is needed.
Example: hard 16 in one deck
Start with one 52-card deck and a hand of 10 + 6. Before card removal, 32 cards would bust a hard 16: four each of 6, 7, 8 and 9, plus sixteen ten-value cards. Your hand has already removed two of those cards.
- Unknown cards: 52 − 2 = 50.
- Bust cards: 32 − 2 = 30.
- Bust probability: 30 / 50 = 60.00%.
If the dealer’s visible card is another 10 and you enter it under “Other known cards,” the probability becomes 29 / 49 = 59.18%. This calculation uses only the listed card values; it does not incorporate information from a dealer blackjack check.
Example: the same total with different cards
In one deck, 8 + 4 is hard 12. Neither card removes a ten-value card, leaving a bust probability of 16 / 50 = 32.00%. With 10 + 2, only fifteen ten-value cards remain, so the probability is 15 / 50 = 30.00%. The total is the same, but the remaining cards differ.
Why a soft hand cannot bust on one hit
A soft hand contains an ace currently counted as 11. If the next card would take the total over 21, that ace becomes 1 instead, reducing the total by ten.
For example, A + 6 is soft 17. Drawing a 10 produces hard 17, not 27. Drawing a 5 produces hard 12. Neither draw busts the hand, but the next decision can be very different. A hand containing an ace is not always soft: A + 6 + 10 is hard 17 because the ace must count as 1.
Bust risk does not tell you whether to hit or stand
Standing prevents you from busting through another draw, but the dealer can still finish with a better hand. Hitting introduces bust risk while giving you a chance to improve. The best decision depends on the dealer’s up-card, the rules and the expected return of the available actions.
An action with negative expected value loses money on average under its model; it does not lose every individual hand. Use the basic strategy calculator for a rules-based action, or the Blackjack Decision EV Calculator to compare the expected returns of different decisions.
Model assumptions and limits
- Standard cards: each deck contains 52 cards, including four of every rank. The tool does not model altered packs such as Spanish 21.
- Known-card information only: finite-deck results depend on the cards you enter. Do not guess unseen discards, burn cards or the dealer’s hole card.
- Unknown cards: absent extra information, unseen cards are treated symmetrically. The denominator is the unknown card pool, not necessarily the physical number still inside the shoe.
- No dealer-peek conditioning: knowing that a dealer showing an ace or ten does not have blackjack can change the conditional probabilities. This tool does not apply that information.
- One-card scope: dealer S17/H17 rules govern the dealer’s later play. They do not change this player one-card calculation when the card information is held fixed.
Frequently asked questions
What is the chance of busting on hard 16?
In the infinite-deck model, hard 16 busts on 6, 7, 8, 9, 10, J, Q or K: 8/13, or 61.54%. In a finite deck, the probability depends on the known cards removed.
Can you bust by hitting a soft 17?
Not on the next card. The ace can change from 11 to 1 if necessary. The resulting hand may become hard, so a later hit can still cause a bust.
Why can two hands with the same total have different bust probabilities?
In a finite deck, the cards in your hand have been removed from the possible next cards. A hand of 10 and 2 removes a ten-value card, while 8 and 4 does not. Both total 12, but their remaining card pools differ.
Is staying at 21 or below the same as winning?
No. You can avoid busting and still lose to the dealer, or tie and receive a push. This calculator measures only what one additional card does to your hand.
Does this calculator show the dealer’s bust probability?
No. A dealer’s eventual bust probability depends on the up-card, drawing rules, available cards and whether the calculation is conditioned on no dealer blackjack. That is a different calculation from a player’s risk on one hit.
Rules and calculation method
Card scoring follows the standard rules described in Bicycle’s blackjack guide: aces count as 1 or 11, and face cards count as 10. The probabilities on this page are calculated by counting eligible next cards, using the formula and worked examples above.