RLCard: A Toolkit for Reinforcement Learning in Card Games

RLCard is a toolkit for Reinforcement Learning (RL) in card games. It supports multiple card environments with easy-to-use interfaces. The goal of RLCard is to bridge reinforcement learning and imperfect information games, and push forward the research of reinforcement learning in domains with multiple agents, large state and action space, and sparse reward. RLCard is developed by DATA Lab at Texas A&M University.


Make sure that you have Python 3.5+ and pip installed. We recommend installing rlcard with pip as follow:

git clone https://github.com/datamllab/rlcard.git
cd rlcard
pip install -e .

or use PyPI with:

pip install rlcard

To use tensorflow implementation, run:

pip install rlcard[tensorflow]

To try out PyTorch implementation for DQN and NFSP, please run:

pip install rlcard[torch]

If you meet any problems when installing PyTorch with the command above, you may follow the instructions on PyTorch official website to manually install PyTorch.


A short example is as below.

import rlcard
from rlcard.agents import RandomAgent

env = rlcard.make('blackjack')

trajectories, payoffs = env.run()

We also recommend the toy examples in Getting Started.


Run examples/leduc_holdem_human.py to play with the pre-trained Leduc Hold’em model. Leduc Hold’em is a simplified version of Texas Hold’em. Rules can be found here.

>> Leduc Hold'em pre-trained model

>> Start a new game!
>> Agent 1 chooses raise

=============== Community Card ===============
===============   Your Hand    ===============
│J        │
│         │
│         │
│    ♥    │
│         │
│         │
│        J│
===============     Chips      ===============
Yours:   +
Agent 1: +++
=========== Actions You Can Choose ===========
0: call, 1: raise, 2: fold

>> You choose action (integer):

Available Environments




Blackjack (wiki, baike)



Leduc Hold’em (paper)



Limit Texas Hold’em (wiki, baike)



Dou Dizhu (wiki, baike)



Simple Dou Dizhu (wiki, baike)



Mahjong (wiki, baike)



No-limit Texas Hold’em (wiki, baike)



UNO (wiki, baike)



Gin Rummy (wiki, baike)




The perfomance is measured by winning rates through tournaments. Example outputs are as follows: Learning Curves

Library Structure

The purposes of the main modules are listed as below:

  • /examples: Examples of using RLCard.

  • /docs: Documentation of RLCard.

  • /tests: Testing scripts for RLCard.

  • /rlcard/agents: Reinforcement learning algorithms and human agents.

  • /rlcard/envs: Environment wrappers (state representation, action encoding etc.)

  • /rlcard/games: Various game engines.

  • /rlcard/models: Model zoo including pre-trained models and rule models.

API Cheat Sheet

How to create an environment

You can use the the following interface to make an environment. You can specify some configurations with a dictionary.

  • env = rlcard.make(env_id, config={}): Make an environment. env_id is a string of a environment; config is a dictionary specifying some environment configurations, which are as follows.

  • seed: Default None. Set a environment local random seed for reproducing the results.

  • env_num: Default 1. It specifies how many environments running in parallel. If the number is larger than 1, then the tasks will be assigned to multiple processes for acceleration.

  • allow_step_back: Defualt False. True if allowing step_back function to traverse backward in the tree.

  • allow_raw_data: Default False. True if allowing raw data in the state.

  • single_agent_mode: Default False. True if using single agent mode, i.e., Gym style interface with other players as pretrained/rule models.

  • active_player: Defualt 0. If single_agent_mode is True, active_player will specify operating on which player in single agent mode.

  • record_action: Default False. If True, a field of action_record will be in the state to record the historical actions. This may be used for human-agent play.

Once the environemnt is made, we can access some information of the game.

  • env.action_num: The number of actions.

  • env.player_num: The number of players.

  • env.state_space: Ther state space of the observations.

  • env.timestep: The number of timesteps stepped by the environment.

What is state in RLCard

State is a Python dictionary. It will always have observation state['obs'] and legal actions state['legal_actions']. If allow_raw_data is True, state will have raw observation state['raw_obs'] and raw legal actions state['raw_legal_actions'].

Basic interfaces

The following interfaces provide a basic usage. It is easy to use but it has assumtions on the agent.

  • env.set_agents(agents): agents is a list of Agent object. The length of the the list should equal to the number of the player in the game.

  • env.run(is_training=False): Run a complete game and return trajectories and payoffs. The function can be used after the set_agents is called. If is_training is True, the function will use step function in the agent to play the game. If is_training is False, eval_step will be called instead.

Advanced interfaces

For advanced usage, the following interfaces allow flexible operations on the game tree. These interfaces do not make any assumtions on the agent.

  • env.reset(): Initialize a game. Return the state and the first player ID.

  • env.step(action, raw_action=False): Take one step in the environment. action can be raw action or integer; raw_action should be True if the action is raw action (string).

  • env.step_back(): Available only when allow_step_back is True. Take one step backward. This can be used for algorithms that operate on the game tree, such as CFR (chance sampling).

  • env.is_over(): Return True if the current game is over/ Return False otherwise.

  • env.get_player_id(): Return the Player ID of the current player.

  • env.get_state(player_id): Return the state corresponds to player_id.

  • env.get_payoffs(): In the end of the game, return a list of payoffs for all the players.

  • env.get_perfect_information(): (Currently only support some of the games) Obtain the perfect information at the current state.

Running with multiple processes

RLCard now supports acceleration with multiple processes. Simply change env_num when making the environment to indicate how many processes would be used. Currenly we only support run() function with multiple processes.


Contribution to this project is greatly appreciated! Please create a issue for feedbacks/bugs. If you want to contribute codes, pleast contact daochen.zha@tamu.edu or khlai037@tamu.edu. We currently have several plans, you can view them on the github page. Please create an issue or contact us through emails if you have other suggestions.


We would like to thank JJ World Network Technology Co.,LTD for the generous support.