What is a blackjack helper?

A tool that tells you the best play for the hand in front of you. Here you tap the dealer's card and yours, and it works out what standing, hitting, doubling, splitting and surrendering are each worth for those exact cards and your table's rules, then shows the one that loses the least. A basic strategy chart gives the same answer for most two-card hands. The helper also uses your exact cards, which matters with three or more: with 6 decks, 4-5-7 against a 10 is better stood on (-53.9% against -54.6%), while the chart says hit on 16.

Is using a blackjack helper allowed?

It depends where you play. At an online casino it comes down to that site's terms, so read what they say about outside software or assistance before you use one at a real-money table. In a land casino it can be a crime: in Nevada, NRS 465.075 makes it unlawful to use, or carry with the intent to use, a device or software designed to obtain an advantage, including one that analyzes the probability of an outcome or a playing or betting strategy, at a licensed casino or at any game a Nevada licensee or its affiliate offers, unless the Gaming Commission allows it. Other states and countries have their own rules. Practising with it at home is not affected by either.

Should you hit or stand on 16 against a 10?

Hit, by a hair, with a two-card 16 and no surrender. With 6 decks, 10-6 against a 10 is -53.5% if you hit and -54.1% if you stand, per bet (after the dealer has checked for blackjack); 9-7 is -53.5% against -53.7%. With three or more cards it can flip: 4-5-7 is better stood on (-53.9% against -54.6%). Where late surrender is allowed, give up half the bet instead: -50.0% beats both.

Should you take insurance in blackjack?

No. Insurance pays 2:1 when the dealer's hole card is a ten, and with 6 decks it loses 7.40% of what you put on it with no other cards seen (7.77% if you hold 10-7, because you hold a ten yourself). It is a separate side bet on the hole card, not protection for your hand. It only pays when more than a third of the cards left are tens, which you can only know by tracking the cards already played.

Why always split 8s but never 10s?

A pair of 8s is 16, the worst total, and two hands starting at 8 do better: against a 10 splitting is -47.5% against -53.5% for hitting, and against an ace -36.5% against -51.4%. Both are losses; splitting loses less. A pair of 10s is 20, which already wins most of the time: against a 6, standing is +70.3% and splitting +56.7%.

Does basic strategy beat the house?

No. It is the play that loses the least, not a winning system. With the default rules (6 decks, dealer stands on soft 17, double after split, 3:2) perfect basic strategy still leaves a house edge of 0.40%: you lose about $0.40 per $100 of starting bets on average. The edge only goes below zero with very favourable rules, such as these same rules dealt from a single deck (-0.18%).

How much bankroll do I need for blackjack?

It depends on how long you play and how much risk of losing it all you accept, because the edge means no bankroll is safe forever. With $500 and $10 a hand for 200 hands at the default rules, the chance of losing it all is 0.25% and the expected result is -$8.07. For a 5% chance of going broke over those 200 hands, bet at most $15 a hand. The session panel below the hand suggests a bet for your balance and risk level, or you can type your own.

Does the number of decks change basic strategy?

Yes, a little. Going from 6 decks to 1 with the same rules changes 14 of the 360 cells in the chart and moves the house edge from 0.40% to -0.18%. Fewer decks mean each card you hold changes the rest of the deck more, and blackjacks are slightly more likely.

Is 6:5 blackjack worth playing?

It costs you. Paying 6 to 5 instead of 3 to 2 on a blackjack adds 1.36% to the house edge with 6 decks (0.40% becomes 1.76%). Nothing else in the game changes, so at the same bet you lose about 4.4 times as much on average.

Blackjack Helper

Tap the dealer's card and your cards to get the best move, with the odds of every option.

18+ · Gambling can be addictive. The house edge means you lose over time.

Dealer

You

Hit

-53.5%

Start

Bet per hand

Risk

Plan

Session odds

Strategy chart

House edge 0.40%

Hard totals

You	2	3	4	5	6	7	8	9	10	A
5-8	H	H	H	H	H	H	H	H	H	H
9	H	Dh	Dh	Dh	Dh	H	H	H	H	H
10	Dh	Dh	Dh	Dh	Dh	Dh	Dh	Dh	H	H
11	Dh	Dh	Dh	Dh	Dh	Dh	Dh	Dh	Dh	H
12	H	H	S	S	S	H	H	H	H	H
13	S	S	S	S	S	H	H	H	H	H
14	S	S	S	S	S	H	H	H	H	H
15	S	S	S	S	S	H	H	H	H	H
16	S	S	S	S	S	H	H	H	H	H
17-21	S	S	S	S	S	S	S	S	S	S

Soft totals

You	2	3	4	5	6	7	8	9	10	A
A,2-3	H	H	H	Dh	Dh	H	H	H	H	H
A,4	H	H	Dh	Dh	Dh	H	H	H	H	H
A,5	H	H	Dh	Dh	Dh	H	H	H	H	H
A,6	H	Dh	Dh	Dh	Dh	H	H	H	H	H
A,7	S	Ds	Ds	Ds	Ds	S	S	H	H	H
A,8-10	S	S	S	S	S	S	S	S	S	S

Pairs

You	2	3	4	5	6	7	8	9	10	A
2,2	P	P	P	P	P	P	H	H	H	H
3,3	P	P	P	P	P	P	H	H	H	H
4,4	H	H	H	P	P	H	H	H	H	H
5,5	Dh	Dh	Dh	Dh	Dh	Dh	Dh	Dh	H	H
6,6	P	P	P	P	P	H	H	H	H	H
7,7	P	P	P	P	P	P	H	H	H	H
8,8	P	P	P	P	P	P	P	P	P	P
9,9	P	P	P	P	P	S	P	P	S	S
10,10	S	S	S	S	S	S	S	S	S	S
A,A	P	P	P	P	P	P	P	P	P	P

HHit
SStand
DhDouble, else hit
DsDouble, else stand
PSplit
RhSurrender, else hit
RsSurrender, else stand
RpSurrender, else split

Basic strategy keeps the house edge as low as these rules allow; it doesn't remove it. Set a budget before you play, and see our responsible gambling page if it stops being fun. 18+.

How to use it

Tap New hand, then three cards on the keypad: the dealer's card, then your two (or type them, like 35q).
Read the move. The chips show what each option is worth, in % of your bet. Tap the move you make; on a split, play each hand in turn.
Add the dealer's other cards if you like: the helper then shows who won.
Tap the result next to the cards. The session balance and history update and the next hand starts.
Below the hand, enter your balance and bet per hand. Pick a risk level to fill in a suggested bet: Low, Medium, High or Degen is a 1%, 5%, 10% or 50% chance of losing the whole balance over the hands you plan.
If your table's rules differ from the default (6 decks, dealer stands on soft 17, blackjack pays 3:2), change them in the settings.

Your bankroll and session

The session panel starts from two numbers: the balance you bring and how much risk of losing all of it you accept. Low, Medium, High and Degen are a 1%, 5%, 10% and 50% chance of going broke, and the suggested bet is sized to keep you there. A bet you type yourself shows as Custom. With the default rules, a $500 balance and 200 hands, that works out to:

Risk level	Chance of going broke	Largest bet ($500, 200 hands)
Low	1%	$11
Medium	5%	$15
High	10%	$17
Degen	50%	$41

Each result you tap moves the balance, and it swings a lot: one hand's result has a standard deviation of 1.15 bets. At $10 a hand for 200 hands, the expected result is -$8.07, and 90% of sessions end between -$275.00 and +$260.00. "Session odds" in the session panel shows the full picture for your numbers: the expected loss, the swing, and your chance of finishing ahead or going broke. While you play, Luck compares your result with what your moves were worth, and Mistakes adds up what you gave away by not taking the best move. Neither changes the next hand: it has the same expected value whatever came before.

How basic strategy works

For every hand against every dealer card there is one play that loses the least over time. The helper works it out for your exact cards, and the chart under it lists it for every hand total.

How to read the strategy chart

Find your hand down the side and the dealer's upcard across the top. Hard hands have no ace, or an ace that has to count as 1. Soft hands have an ace counted as 11, so one more card can't bust you. Pairs are the rows for your first two cards when they match.

Two letters mean a first choice and a fallback. "Double, else hit" means double when the rules let you (usually only on your first two cards) and hit when they don't; "surrender, else hit" is the same for surrender. The chart is the best move for the hand total, averaged over the two-card hands that make it, which is how basic strategy charts are built. The helper uses your exact cards, so a three-card 16 can get a different answer from a two-card one.

Why the deck count and rules change the moves

Every card you and the dealer hold is gone from the shoe. With 6 decks that barely matters; with 1 deck it changes 14 of the 360 cells in the chart (same rules otherwise). When the dealer hits soft 17 instead of standing, the dealer busts a little more often and makes a few more strong totals, and 3 cells change with 6 decks.

Show the cells that change

Hand	Dealer	6 decks	1 deck
Hard 8	5	hit	double (else hit)
Hard 8	6	hit	double (else hit)
Hard 9	2	hit	double (else hit)
Hard 11	A	hit	double (else hit)
A,2	4	hit	double (else hit)
A,3	4	hit	double (else hit)
A,6	2	hit	double (else hit)
A,7	A	hit	stand
A,8	6	stand	double (else stand)
3,3	8	hit	split
4,4	4	hit	split
6,6	7	hit	split
7,7	8	hit	split
7,7	10	hit	stand

Hand	Dealer	Stands on soft 17	Hits soft 17
Hard 11	A	hit	double (else hit)
A,7	2	stand	double (else stand)
A,8	6	stand	double (else stand)

House edge by rules

The house edge with perfect play, as a % of your starting bet, changing one rule at a time from the default. Doubles and splits put more money on the table, so the loss per amount wagered is lower than these figures; per hand you start, this is what you lose on average.

Rules	House edge
Default: 6 decks, dealer stands on soft 17, double any two, double after split, peek, 3:2	0.40%
Dealer hits soft 17	0.62%
No double after split	0.54%
Double on 9 to 11 only	0.50%
Late surrender	0.33%
No hole card (European, dealer doesn't peek)	0.51%
8 decks	0.43%
2 decks	0.18%
1 deck	-0.18%
Infinite deck (reshuffled every hand)	0.51%
Blackjack pays 6:5	1.76%

Computed by our calculator; they agree with the Wizard of Odds house edge calculator to within 0.003 percentage points for the 15 rule sets in our test script. A negative edge means the player has the edge.

Insurance

When the dealer shows an ace you can bet up to half your stake that the hole card is a ten. It pays 2:1, so it breaks even only if more than a third of the unseen cards are tens. In a 6-deck shoe with the dealer's ace out, 96 of the 311 unseen cards are tens (30.9%), a bit less than a third, which is why insurance loses 7.40% of the insurance bet with 6 decks. The helper shows the figure for the cards you've entered, and says to decline it.

6:5 vs 3:2 blackjack

A blackjack pays 1.5 times your bet at 3:2 and 1.2 times at 6:5. You get a blackjack the dealer doesn't match in 4.53% of hands with 6 decks (about 1 in 22), so the difference is:

0.3 × P(you get blackjack and the dealer doesn't) = 1.36% of every bet with 6 decks

That takes the default game from 0.40% to 1.76%, more than every other rule in the table above. The strategy doesn't change, only the payout.

Card counting, and devices at the table

Counting keeps track of the cards already dealt to spot when the cards left favour you. According to the Wizard of Odds, counting in your head isn't cheating in the legal sense (using a device is), but a casino that spots it can respond, from worse table conditions to shuffling or barring you. In Nevada, NRS 465.075 makes it unlawful to use a device or software that analyzes probabilities or playing strategy at a licensed casino's games, so a helper like this one stays off the table there. Counting needs cards that stay out of play: a continuous shuffling machine, or an online game that draws every card from a fresh infinite deck, leaves nothing to count, and the infinite-deck setting here models them. An online game that reshuffles a 6-deck shoe before every hand leaves nothing to count either, but it plays like the 6-deck setting.

For the maths nerds: how this calculator works

Every value comes from an exact calculation, not a simulation. For your hand and the dealer's upcard, the calculator removes those cards from the shoe and works out the dealer's final total probabilities for every way the player's hand can go, then picks the best action at every step. What that means for the numbers:

The expected values are composition dependent: they use your exact cards. The chart averages them over the two-card hands for each total. When the dealer peeks, values are given after the peek (the dealer doesn't have blackjack), as on standard charts.
Splits are played exactly for each hand, with both pair cards out of the shoe, but the cards the other split hands draw are not removed. That is the usual simplification, and our split values are within 0.006 of a bet of the Wizard of Odds's published ones (which use a similar simplification).
Our test script compares the chart cell by cell with the Wizard of Odds strategy calculator for 11 rule sets and matches all 360 cells in 10 of them. The other one (2 decks, dealer hits soft 17, double after split, late surrender) differs on one cell, 8-8 against an ace: the Wizard's chart says surrender, and its own expected values table gives splitting -0.4936, better than surrender at -0.5, which is what we show.
With no hole card, late surrender here gives back half the bet only if the dealer doesn't turn out to have blackjack; a dealer blackjack still takes the whole bet. The Wizard of Odds house edge calculator works the same way, and our edges for 4 such rule sets agree with it. His strategy chart's European columns instead mark surrender as if it beat a dealer blackjack (it suggests surrendering hard 5 against an ace, for example), so for those rule sets we compare the chart that way, as a check of the engine, not of the page's advice.
Every card on the table (your hand, the dealer's card, your other split hands) is taken out of the shoe. To keep the page fast, cards you would draw after the first 6 in a calculation come from the shoe as it was; over every two-card hand against every dealer card with 1, 2 and 6 decks, that moves no expected value by more than 0.00001 of a bet.
The bankroll figures use the full spread of one hand's result (blackjacks, doubles, splits, surrender): standard deviation 1.154 bets and 1.132 bets on the table per hand with the default rules, both checked against 4,000,000simulated hands. The spread is worked out on an infinite deck for your rules, with its average set to the house edge for your deck count. The chance of going broke follows every possible balance hand by hand; very long sessions use the normal approximation and say so.

Blackjack is still gambling: the best strategy only lowers what you lose. Set a budget before you play, and see our responsible gambling page if it stops being fun. Looking for a table? See our crypto blackjack sites.

Where to use it

Compare sites on our CS2 roulette sites, crypto casinos and CS2 betting sites lists, and check a site's rolls with the provably fair verifier. Check what a game keeps with the house edge calculator. Set a budget first, and see our responsible gambling page if it stops being fun. 18+ only.

By Matt (MattCS), founder and lead reviewer. The strategy and house edge are exact for the rules you pick, and checked against the Wizard of Odds charts and simulation in our test script. Last updated 31 October 2026.

FAQ

What is a blackjack helper?: A tool that tells you the best play for the hand in front of you. Here you tap the dealer's card and yours, and it works out what standing, hitting, doubling, splitting and surrendering are each worth for those exact cards and your table's rules, then shows the one that loses the least. A basic strategy chart gives the same answer for most two-card hands. The helper also uses your exact cards, which matters with three or more: with 6 decks, 4-5-7 against a 10 is better stood on (-53.9% against -54.6%), while the chart says hit on 16.
Is using a blackjack helper allowed?: It depends where you play. At an online casino it comes down to that site's terms, so read what they say about outside software or assistance before you use one at a real-money table. In a land casino it can be a crime: in Nevada, NRS 465.075 makes it unlawful to use, or carry with the intent to use, a device or software designed to obtain an advantage, including one that analyzes the probability of an outcome or a playing or betting strategy, at a licensed casino or at any game a Nevada licensee or its affiliate offers, unless the Gaming Commission allows it. Other states and countries have their own rules. Practising with it at home is not affected by either.
Should you hit or stand on 16 against a 10?: Hit, by a hair, with a two-card 16 and no surrender. With 6 decks, 10-6 against a 10 is -53.5% if you hit and -54.1% if you stand, per bet (after the dealer has checked for blackjack); 9-7 is -53.5% against -53.7%. With three or more cards it can flip: 4-5-7 is better stood on (-53.9% against -54.6%). Where late surrender is allowed, give up half the bet instead: -50.0% beats both.
Should you take insurance in blackjack?: No. Insurance pays 2:1 when the dealer's hole card is a ten, and with 6 decks it loses 7.40% of what you put on it with no other cards seen (7.77% if you hold 10-7, because you hold a ten yourself). It is a separate side bet on the hole card, not protection for your hand. It only pays when more than a third of the cards left are tens, which you can only know by tracking the cards already played.
Why always split 8s but never 10s?: A pair of 8s is 16, the worst total, and two hands starting at 8 do better: against a 10 splitting is -47.5% against -53.5% for hitting, and against an ace -36.5% against -51.4%. Both are losses; splitting loses less. A pair of 10s is 20, which already wins most of the time: against a 6, standing is +70.3% and splitting +56.7%.
Does basic strategy beat the house?: No. It is the play that loses the least, not a winning system. With the default rules (6 decks, dealer stands on soft 17, double after split, 3:2) perfect basic strategy still leaves a house edge of 0.40%: you lose about $0.40 per $100 of starting bets on average. The edge only goes below zero with very favourable rules, such as these same rules dealt from a single deck (-0.18%).
How much bankroll do I need for blackjack?: It depends on how long you play and how much risk of losing it all you accept, because the edge means no bankroll is safe forever. With $500 and $10 a hand for 200 hands at the default rules, the chance of losing it all is 0.25% and the expected result is -$8.07. For a 5% chance of going broke over those 200 hands, bet at most $15 a hand. The session panel below the hand suggests a bet for your balance and risk level, or you can type your own.
Does the number of decks change basic strategy?: Yes, a little. Going from 6 decks to 1 with the same rules changes 14 of the 360 cells in the chart and moves the house edge from 0.40% to -0.18%. Fewer decks mean each card you hold changes the rest of the deck more, and blackjacks are slightly more likely.
Is 6:5 blackjack worth playing?: It costs you. Paying 6 to 5 instead of 3 to 2 on a blackjack adds 1.36% to the house edge with 6 decks (0.40% becomes 1.76%). Nothing else in the game changes, so at the same bet you lose about 4.4 times as much on average.

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