The 21+3 is the most popular side bet in modern Blackjack. It combines your first two cards and the Dealer’s up-card to form a three-card Poker hand. It adds excitement to the grind, offering payouts up to 100:1.
However, not all 21+3 tables are created equal. A casino in Las Vegas might use a paytable that gives the house a 3% edge, while an online casino might use a slightly different table that spikes the edge to over 7%. Our 21+3 Side Bet Calculator allows you to input the specific payouts of your table to determine the exact Return to Player (RTP) and House Edge.
21+3 Side Bet Analyzer
Odds CalculatorHow to Use the Calculator
This tool is designed to audit the fairness of the side bet you are planning to play. Here is how to configure it:
- Select Number of Decks: This heavily influences the probability of hitting specific hands.
- Note: In a Single Deck game, “Suited Trips” are mathematically impossible (as there is only one King of Hearts in the deck).
- Choose a Paytable Preset:
- Standard (9-6-4): The most common “fair” version found in physical casinos.
- Vegas / Evolution: The volatile version with high payouts for Suited Trips (100:1) but lower payouts for Flushes.
- Flat: The old-school version that pays 9:1 for any winning hand.
- Customize the Payouts: If your local casino pays differently (e.g., only 4:1 for a Flush), edit the input field manually.
- Analyze the House Edge: Look at the result at the bottom.
- Green (0-3%): A great bet (for a side bet).
- Red (>8%): A “sucker bet.” Avoid playing this table.
Related Tools: Side bets are fun, but the main money is made in the base game. Use the Blackjack Payout Calculator to check your main winnings. If you are counting cards to beat the side bet, verify your advantage with the True Count Calculator.
Real-World Examples: The “Flush” Trap
Casinos often subtly change one number on the paytable to drastically increase their profits. Most players never notice.
Example 1: The Standard Table
You play a 6-deck game with the standard “9-6-4” paytable (Flush pays 5:1, Straight 10:1, etc.).
- House Edge: ~3.2%.
- Verdict: This is a reasonable “entertainment” bet. It won’t drain your bankroll too quickly.
Example 2: The “Short Pay” Flush
You find a table that looks identical, but you notice the Flush pays 4:1 instead of 5:1.
- Impact: Since the Flush is the most common winning hand (occurring ~5.8% of the time), lowering the payout by just 1 unit is devastating.
- House Edge: Jumps to over 8.5%.
- Verdict: This is a bad bet. By using the calculator, you can spot this “trap” and save your chips for the main game.
Frequently Asked Questions (FAQ)
What are the winning hands in 21+3?
The hands are ranked from highest to lowest payout:
- Suited Trips: Three identical cards (e.g., 3 Jacks of Spades).
- Straight Flush: Consecutive rank, same suit.
- Three of a Kind: Same rank, mixed suits.
- Straight: Consecutive rank, mixed suits.
- Flush: Three cards of the same suit.
Can I count cards to beat the 21+3 side bet?
Yes. While the main game relies on High/Low cards, the 21+3 bet relies on “Suit Density.” Advanced counters track suits to predict Flushes. However, this is much harder than standard card counting and requires a specific system.
Why does the number of decks matter?
Probabilities change with deck depth. For example, Suited Trips are impossible in a 1-Deck or 2-Deck game because there aren’t three identical cards available. If you play 21+3 on a Single Deck game with a standard paytable, the House Edge is astronomical because you can never hit the jackpot hand.