Miss any of our Open RFC calls?Watch the recordings here! »


3.0.2 • Public • Published

Football Simulation Engine


A recent update to 'startPOS' and 'relativePOS' to 'currentPOS' and 'intentPOS' respectively are MAJOR changes in v3.0.0 and beyond. This change is not yet in NPM but will be as of the release of v3.0.0

If you wish to continue using 'startPOS' and 'relativePOS' you should use v2.2.0 https://github.com/GallagherAiden/footballSimulationEngine/releases/tag/v2.2.0


This module was designed to allow the simulation of football (soccer) matches between two teams. This module allows for an iterative football match to be played out given initial "state" of players.

The module consists of three functions that:

  • Initiate a match
  • complete an iteration / movement
  • switch team sides / start second half

For examples of how this module can be used, see:

Latest Version (3.0.0)

  • altered 'startPOS' to 'currentPOS' to better reflect what the variable is used for
  • altered 'relativePOS' to 'intentPOS' to better reflect what what the variable is used for
  • added 100+ test cases
  • cleaned 'setPositions.js' and created/cleaned 'setFreekicks.js' to improve readability and reduce duplication
  • improvement to corners by putting players in the box
  • players with red cards are removed from the pitch
  • penalty taking improvements
  • skills used more intensively i.e. shooting can be both on/off target determined by skill
  • add player specific stats including tackles, passes, shots, saves and goals
  • Full and Past changelogs are available here.


Make sure your version of Node.js is at least 7.6.0. (The 'async/await' function is used)

npm install --save footballsimulationengine

Initiate Game

This function is a promise that expects two teams and pitch information in JSON format (JSON format is described below). The function will return match details including player start positions, match statistics, ball position and an iteration log.

Example Call

initiateGame(team1, team2, pitch).then(function(matchDetails){
  console.error("Error: ", error);

Play Iteration

This function is a promise that expects a single JSON input. This input will match the output of the initiate game function and will make the next move of both teams, resolving the final position of each player.

Example Call

playIteration(matchDetails).then(function (matchDetails) {
  console.error("Error: ", error);

Start Second Half (Switch Sides)

This function is a promise that switches the side of each team, as happens typically at the end of a half. This uses the output from either an initiate game or a play iteration.

Example Call

startSecondHalf(matchDetails).then(function (matchDetails) {
  console.error("Error: ", error);


  • Users can determine how many iterations make a half
  • Test data found in init_config is the data used for testing
  • Iteration logs give an overview of what has happened in the iteration
  • Uncomment console.log(output) to receive iteration by iteration information of each players iteration action, movement, original position and final position (start POS).

Additional Information

  • Get in touch with any questions email
  • See a match example here
  • Raise issues in GitHub


Examples are baked into the file system (>v2.1.0) in the init_config directory:

  • index.js : example function usages
  • team1.json : example json for a primary team
  • team2.json : example json for a secondary team
  • pitch.json : example json for pitch details
  • iteration.json : shows what the overall output given for each iteration

Example Team JSON

Each team must have the following information and contain 11 players.

  • A start position for each player, with both teams given start positions as if they were the team at the top of a vertical pitch (shooting to the bottom of the screen). The currentPOS object should be [widthPosition, heightPosition] where the height placement should not be a greater number than half the pitch height.
  • skills should not exceed 100
  • skill.jumping refers to height a player can jump in centimetres (so can and probably should be greater than 100).
  "name": "Team1",
  "players": [{
      "name": "Player",
      "position": "GK",
      "rating": "99",
      "skill": {
        "passing": "99",
        "shooting": "99",
        "tackling": "99",
        "saving": "99",
        "agility": "99",
        "strength": "99",
        "penalty_taking": "99",
        "jumping": "300"
      "currentPOS": [60,0],
      "fitness": 100,
      "injured": false
  "manager": "Aiden"

Example Pitch JSON

Pitch has been tested for width of 120 - 680 and height of 600 - 1050. The below is the current provided pitch size.

    "pitchWidth": 680,
    "pitchHeight": 1050

Example Match Details

v2.1.0 - ball movement added so that a kicked ball makes movements over time. This can be seen in 'ball.ballOverIterations'. If empty, no new ball movements will occur. Deflections may occur as players move over iterations.

{ kickOffTeam:
   { name: 'Team1',
      [ [Object],
        [Object] ],
     manager: 'Aiden'
     intent: 'defend' },
   { name: 'Team2',
      [ [Object],
        [Object] ],
     manager: 'Joe',
     intent: 'attack' },
  pitchSize: [ 120, 600 ],
   { position: [ 76, 314, 0 ],
     withPlayer: true,
     Player: 'Joe Bloggs',
     withTeam: 'Team2',
     direction: 'south' },
     ballOverIterations: []
  half: 1,
   { goals: 0,
     shots: 0,
     corners: 0,
     freekicks: 0,
     penalties: 0,
     fouls: 0 },
   { goals: 0,
     shots: 0,
     corners: 0,
     freekicks: 0,
     penalties: 0,
     fouls: 0 },
   [ 'Closest Player to ball: Aiden Gallagher',
     'Closest Player to ball: Joe Bloggs' ] }

Example Player JSON (after game initiated):

Any and all player objects may be altered between iterations. Including the relative position, origin position and action. Action should be - 'null' if the simulation is to be run normally. This can be overriden with any of the following actions: 'shoot', 'throughBall', 'pass', 'cross', 'tackle', 'intercept', 'slide', 'run', 'sprint', 'cleared', 'boot'. The player must have the ball in order to complete ball specific actions like 'shoot'. Any invalid actions will result in the simulation running as normal.

{ name: 'Louise Johnson',
    position: 'ST',
    rating: '88',
     { passing: '20',
       shooting: '20',
       tackling: '20',
       saving: '20',
       agility: '20',
       strength: '20',
       penalty_taking: '20',
       jumping: '280' },
    currentPOS: [ 60, 300 ],
    fitness: 100,
    injured: false,
    originPOS: [ 70, 270 ],
    intentPOS: [ 70, 270 ],
    action: 'none',
    offside: false,
    cards: {
      yellow: 0,
      red: 0
    hasBall: true }


npm i footballsimulationengine

DownloadsWeekly Downloads






Unpacked Size

2.55 MB

Total Files


Last publish


  • avatar