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Blackjack IndexFree Online Blackjack Simulator & Strategy Lab

Long-run laboratory · repeatable trials

Blackjack long-run simulator and variance calculator.

Configure independent blackjack sessions, then inspect bankroll paths, drawdown, outcome ranges and convergence with the rules, seed and method kept in view.

Preview dataset

A fixed specimen shows the workspace before an authoritative run starts.

Illustrative workspace

The visible charts are a fixed interface preview. They are not a live simulation, forecast or gambling result.

Long-run summary

Mean return
−3.4 creditsper 500-hand specimen session
Middle 80% range
−88 to +76virtual credits at session end
Median max drawdown
41 creditsfixed preview path set
Completed trials
10,000illustrative only

Bankroll paths

A selected specimen path shows how cumulative virtual-credit return can move across resolved hands.

Virtual credits
Independent-session preview v1
Virtual-credit profit
Bankroll pathsSelected specimen path · fixed interface data 21 source · 21 rendered
Virtual-credit profitResolved hands0500
Focus or tap a point to inspect its exact preview value.

illustrative-long-run-workspace-v1

Open semantic data table
Resolved handsVirtual-credit profit
0
4
-8
12
6
-19
-7
-24
-15
3
-9
-2
-28
-17
-31
-12
-20
-6
-18
-4
-14

Mean return convergence

The running estimate narrows toward its disclosed preview band as more independent trials are included.

Virtual credits per session
Independent-session preview v1
Mean session returnIllustrative range
Mean return convergenceIllustrative estimate and descriptive band 8 source · 8 rendered
Mean session returnIndependent trials included10010,000
Focus or tap a point to inspect its exact preview value.

illustrative-long-run-workspace-v1

Open semantic data table
Independent trials includedMean session return
-7.8
-5.9
-5.1
-4.5
-3.9
-3.6
-3.5
-3.4

Drawdown profile

Distance below the prior path peak makes the depth and duration of losing sequences visible.

Virtual credits below peak
Independent-session preview v1
Drawdown from prior peak
Drawdown profileSelected specimen path · fixed interface data 21 source · 21 rendered
Drawdown from prior peakResolved hands0500
Focus or tap a point to inspect its exact preview value.

illustrative-long-run-workspace-v1

Open semantic data table
Resolved handsDrawdown from prior peak
0
0
-12
0
-6
-31
-19
-36
-27
-9
-21
-14
-40
-29
-43
-24
-32
-18
-30
-16
-26

Trial outcome range

Independent session endings are grouped into descriptive virtual-credit bands.

Outcome bandTrialsShareInterpretation
Below −80 credits9009%Lower outcome tail
−80 to −20 credits2,30023%Negative session range
−20 to +20 credits3,90039%Near-even session range
+20 to +80 credits2,20022%Positive session range
Above +80 credits7007%Upper outcome tail

Method and reproducibility

A result is only meaningful with its rules, strategy, seed, trial count and implementation identities attached.

Illustrative workspace

The visible charts are a fixed interface preview. They are not a live simulation, forecast or gambling result.

Method
Fixed editorial specimen
Model
Independent-session preview v1
Ruleset
American Blackjack · 6 decks · dealer stands on soft 17 · double after split
Seed
blackjack-index-preview-v1
Trials
10,000 · 500 hands per independent trial
Confidence
Illustrative band · not statistically estimated
Dataset
illustrative-long-run-workspace-v1
Engine
Not connected
Worker
Not connected