↻ This simulator works best in
landscape mode
— rotate your device for the full experience.
✕
Axelrod's
Iterative Prisoner's Dilemma
The Prisoner's Dilemma
Each prisoner chooses
Cooperate (C)
or
Defect (D)
.
Defection gives a
higher short-term reward
.
Repeated interactions can make
cooperation worthwhile
.
Axelrod's Tournament
This simulator recreates
Robert Axelrod's famous 1980
Iterative Prisoner's Dilemma tournament.
Select
10 strategies
and run your own tournament.
Compare scores to discover which strategies
succeed over time
.
The Big Question
Who wins: the selfish, the forgiving, or the cooperative?
Payoff Points
🤝 C × C
+3 / +3 pts
Mutual trust
😇 C × D
+0 / +5 pts
Sucker's payoff
😈 D × C
+5 / +0 pts
Temptation
💀 D × D
+1 / +1 pts
Mutual punishment
Build Your Strategies
Game
Rules
Run
Tourney
Stage 1: Understanding Strategies in Prisoner's Dilemma
Strategy Definition
ⓘ
Strategy description, broad Nice/Nasty classification, attribute tags and 4-quadrant attribute scores (Nice, Retaliatory, Forgiving, Clear out of 100).
Compare Strategies — Live Preview
ⓘ
Simulate a head-to-head match between any two strategies before the tournament. Results appear round by round.
Select Strategies
ⓘ
Axelrod's original 15 strategies: Tit for Tat, Tideman & Chieruzzi, Nydegger, Grofman, Shubik, Stein & Rapoport, Friedman, Davis, Graaskamp, Downing, Feld, Joss, Tullock, Name Withheld (Random), Two Tits for a Tat.
— Use dropdown to select strategy —
Use dropdown to select strategy
Vs
Rounds:
5 rounds
10 rounds
20 rounds
50 rounds
100 rounds
▶ Live Preview
Strategy A Score
—
Strategy B Score
—
Select two strategies and click Live Preview
🎲 Random
✋ Manual
Nice
Nasty
Selected:
0
/ 10
Back
Stage 2: Tournament Mode — Iterative Prisoner's Dilemma
Number of Rounds
Run Tournament
Match Results
ⓘ
Every head-to-head match. Filter by strategy. Shows scores and winner for each match.
All matches
Run Tournament
to see results
Points Table — Round by Round
ⓘ
Points per strategy per round. Columns: Position | Prev. Position | Strategy | Movement | Points Bar | Total Pts | #Wins
◀ Prev
Next ▶
Round 0 / 0
Pos.
Prev.
Strategy
Tournament Points
Pts
#Wins
Run Tournament
to start
Tournament Analysis
ⓘ
Auto-generated insights from tournament results.
Run Tournament
to see insights