Config with .env

You can use a .env file to store API keys and other settings for the models you use with aider. You can also set many general aider options in the .env file.
Aider will look for a .env file in these locations:
Your home directory.
The root of your git repo.
The current directory.
As specified with the --env-file <filename> parameter.
If the files above exist, they will be loaded in that order. Files loaded last will take priority.
Storing LLM keys

Aider has special support for providing OpenAI and Anthropic API keys via command line switches and yaml config file. All other LLM providers must have their keys and settings specified in environment variables. This can be done in your shell, or by using a .env file.
Sample .env file

Below is a sample .env file, which you can also download from GitHub.
##########################################################
# Sample aider .env file.
# Place at the root of your git repo.
# Or use `aider --env <fname>` to specify.
##########################################################

#################
# LLM parameters:
#
# Include xxx_API_KEY parameters and other params needed for your LLMs.
# See https://aider.chat/docs/llms.html for details.

## OpenAI
#OPENAI_API_KEY=

## Anthropic
#ANTHROPIC_API_KEY=

##...

#######
# Main:

## Specify the OpenAI API key
#OPENAI_API_KEY=

## Specify the Anthropic API key
#ANTHROPIC_API_KEY=

## Specify the model to use for the main chat
#AIDER_MODEL=

## Use claude-3-opus-20240229 model for the main chat
#AIDER_OPUS=

## Use claude-3-5-sonnet-20241022 model for the main chat
#AIDER_SONNET=

## Use claude-3-5-haiku-20241022 model for the main chat
#AIDER_HAIKU=

## Use gpt-4-0613 model for the main chat
#AIDER_4=

## Use gpt-4o-2024-08-06 model for the main chat
#AIDER_4O=

## Use gpt-4o-mini model for the main chat
#AIDER_MINI=

## Use gpt-4-1106-preview model for the main chat
#AIDER_4_TURBO=

## Use gpt-3.5-turbo model for the main chat
#AIDER_35TURBO=

## Use deepseek/deepseek-coder model for the main chat
#AIDER_DEEPSEEK=

## Use o1-mini model for the main chat
#AIDER_O1_MINI=

## Use o1-preview model for the main chat
#AIDER_O1_PREVIEW=

#################
# Model Settings:

## List known models which match the (partial) MODEL name
#AIDER_LIST_MODELS=

## Specify the api base url
#OPENAI_API_BASE=

## Specify the api_type
#OPENAI_API_TYPE=

## Specify the api_version
#OPENAI_API_VERSION=

## Specify the deployment_id
#OPENAI_API_DEPLOYMENT_ID=

## Specify the OpenAI organization ID
#OPENAI_ORGANIZATION_ID=

## Specify a file with aider model settings for unknown models
#AIDER_MODEL_SETTINGS_FILE=.aider.model.settings.yml

## Specify a file with context window and costs for unknown models
#AIDER_MODEL_METADATA_FILE=.aider.model.metadata.json

## Verify the SSL cert when connecting to models (default: True)
#AIDER_VERIFY_SSL=true

## Specify what edit format the LLM should use (default depends on model)
#AIDER_EDIT_FORMAT=

## Use architect edit format for the main chat
#AIDER_ARCHITECT=

## Specify the model to use for commit messages and chat history summarization (default depends on --model)
#AIDER_WEAK_MODEL=

## Specify the model to use for editor tasks (default depends on --model)
#AIDER_EDITOR_MODEL=

## Specify the edit format for the editor model (default: depends on editor model)
#AIDER_EDITOR_EDIT_FORMAT=

## Only work with models that have meta-data available (default: True)
#AIDER_SHOW_MODEL_WARNINGS=true

## Soft limit on tokens for chat history, after which summarization begins. If unspecified, defaults to the model's max_chat_history_tokens.
#AIDER_MAX_CHAT_HISTORY_TOKENS=

## Specify the .env file to load (default: .env in git root)
#AIDER_ENV_FILE=.env

#################
# Cache Settings:

## Enable caching of prompts (default: False)
#AIDER_CACHE_PROMPTS=false

## Number of times to ping at 5min intervals to keep prompt cache warm (default: 0)
#AIDER_CACHE_KEEPALIVE_PINGS=false

###################
# Repomap Settings:

## Suggested number of tokens to use for repo map, use 0 to disable (default: 1024)
#AIDER_MAP_TOKENS=

## Control how often the repo map is refreshed. Options: auto, always, files, manual (default: auto)
#AIDER_MAP_REFRESH=auto

## Multiplier for map tokens when no files are specified (default: 2)
#AIDER_MAP_MULTIPLIER_NO_FILES=true

################
# History Files:

## Specify the chat input history file (default: .aider.input.history)
#AIDER_INPUT_HISTORY_FILE=.aider.input.history

## Specify the chat history file (default: .aider.chat.history.md)
#AIDER_CHAT_HISTORY_FILE=.aider.chat.history.md

## Restore the previous chat history messages (default: False)
#AIDER_RESTORE_CHAT_HISTORY=false

## Log the conversation with the LLM to this file (for example, .aider.llm.history)
#AIDER_LLM_HISTORY_FILE=

##################
# Output Settings:

## Use colors suitable for a dark terminal background (default: False)
#AIDER_DARK_MODE=false

## Use colors suitable for a light terminal background (default: False)
#AIDER_LIGHT_MODE=false

## Enable/disable pretty, colorized output (default: True)
#AIDER_PRETTY=true

## Enable/disable streaming responses (default: True)
#AIDER_STREAM=true

## Set the color for user input (default: #00cc00)
#AIDER_USER_INPUT_COLOR=#00cc00

## Set the color for tool output (default: None)
#AIDER_TOOL_OUTPUT_COLOR=

## Set the color for tool error messages (default: #FF2222)
#AIDER_TOOL_ERROR_COLOR=#FF2222

## Set the color for tool warning messages (default: #FFA500)
#AIDER_TOOL_WARNING_COLOR=#FFA500

## Set the color for assistant output (default: #0088ff)
#AIDER_ASSISTANT_OUTPUT_COLOR=#0088ff

## Set the color for the completion menu (default: terminal's default text color)
#AIDER_COMPLETION_MENU_COLOR=

## Set the background color for the completion menu (default: terminal's default background color)
#AIDER_COMPLETION_MENU_BG_COLOR=

## Set the color for the current item in the completion menu (default: terminal's default background color)
#AIDER_COMPLETION_MENU_CURRENT_COLOR=

## Set the background color for the current item in the completion menu (default: terminal's default text color)
#AIDER_COMPLETION_MENU_CURRENT_BG_COLOR=

## Set the markdown code theme (default: default, other options include monokai, solarized-dark, solarized-light)
#AIDER_CODE_THEME=default

## Show diffs when committing changes (default: False)
#AIDER_SHOW_DIFFS=false

###############
# Git Settings:

## Enable/disable looking for a git repo (default: True)
#AIDER_GIT=true

## Enable/disable adding .aider* to .gitignore (default: True)
#AIDER_GITIGNORE=true

## Specify the aider ignore file (default: .aiderignore in git root)
#AIDER_AIDERIGNORE=.aiderignore

## Only consider files in the current subtree of the git repository
#AIDER_SUBTREE_ONLY=false

## Enable/disable auto commit of LLM changes (default: True)
#AIDER_AUTO_COMMITS=true

## Enable/disable commits when repo is found dirty (default: True)
#AIDER_DIRTY_COMMITS=true

## Attribute aider code changes in the git author name (default: True)
#AIDER_ATTRIBUTE_AUTHOR=true

## Attribute aider commits in the git committer name (default: True)
#AIDER_ATTRIBUTE_COMMITTER=true

## Prefix commit messages with 'aider: ' if aider authored the changes (default: False)
#AIDER_ATTRIBUTE_COMMIT_MESSAGE_AUTHOR=false

## Prefix all commit messages with 'aider: ' (default: False)
#AIDER_ATTRIBUTE_COMMIT_MESSAGE_COMMITTER=false

## Commit all pending changes with a suitable commit message, then exit
#AIDER_COMMIT=false

## Specify a custom prompt for generating commit messages
#AIDER_COMMIT_PROMPT=

## Perform a dry run without modifying files (default: False)
#AIDER_DRY_RUN=false

## Skip the sanity check for the git repository (default: False)
#AIDER_SKIP_SANITY_CHECK_REPO=false

########################
# Fixing and committing:

## Lint and fix provided files, or dirty files if none provided
#AIDER_LINT=false

## Specify lint commands to run for different languages, eg: "python: flake8 --select=..." (can be used multiple times)
#AIDER_LINT_CMD=

## Enable/disable automatic linting after changes (default: True)
#AIDER_AUTO_LINT=true

## Specify command to run tests
#AIDER_TEST_CMD=

## Enable/disable automatic testing after changes (default: False)
#AIDER_AUTO_TEST=false

## Run tests and fix problems found
#AIDER_TEST=false

############
# Analytics:

## Enable/disable analytics for current session (default: random)
#AIDER_ANALYTICS=

## Specify a file to log analytics events
#AIDER_ANALYTICS_LOG=

## Permanently disable analytics
#AIDER_ANALYTICS_DISABLE=false

#################
# Other Settings:

## specify a file to edit (can be used multiple times)
#AIDER_FILE=

## specify a read-only file (can be used multiple times)
#AIDER_READ=

## Use VI editing mode in the terminal (default: False)
#AIDER_VIM=false

## Specify the language to use in the chat (default: None, uses system settings)
#AIDER_CHAT_LANGUAGE=

## Check for updates and return status in the exit code
#AIDER_JUST_CHECK_UPDATE=false

## Check for new aider versions on launch
#AIDER_CHECK_UPDATE=true

## Show release notes on first run of new version (default: None, ask user)
#AIDER_SHOW_RELEASE_NOTES=

## Install the latest version from the main branch
#AIDER_INSTALL_MAIN_BRANCH=false

## Upgrade aider to the latest version from PyPI
#AIDER_UPGRADE=false

## Apply the changes from the given file instead of running the chat (debug)
#AIDER_APPLY=

## Apply clipboard contents as edits using the main model's editor format
#AIDER_APPLY_CLIPBOARD_EDITS=false

## Always say yes to every confirmation
#AIDER_YES_ALWAYS=

## Enable verbose output
#AIDER_VERBOSE=false

## Print the repo map and exit (debug)
#AIDER_SHOW_REPO_MAP=false

## Print the system prompts and exit (debug)
#AIDER_SHOW_PROMPTS=false

## Do all startup activities then exit before accepting user input (debug)
#AIDER_EXIT=false

## Specify a single message to send the LLM, process reply then exit (disables chat mode)
#AIDER_MESSAGE=

## Specify a file containing the message to send the LLM, process reply, then exit (disables chat mode)
#AIDER_MESSAGE_FILE=

## Load and execute /commands from a file on launch
#AIDER_LOAD=

## Specify the encoding for input and output (default: utf-8)
#AIDER_ENCODING=utf-8

## Run aider in your browser (default: False)
#AIDER_GUI=false

## Enable/disable suggesting shell commands (default: True)
#AIDER_SUGGEST_SHELL_COMMANDS=true

## Enable/disable fancy input with history and completion (default: True)
#AIDER_FANCY_INPUT=true

#################
# Voice Settings:

## Audio format for voice recording (default: wav). webm and mp3 require ffmpeg
#AIDER_VOICE_FORMAT=wav

## Specify the language for voice using ISO 639-1 code (default: auto)
#AIDER_VOICE_LANGUAGE=en