---
page_title: Terraform CLI configuration overview
description: >-
  The CLI configuration file and supported Terraform environment variables let you customize Terraform CLI behavior. 
---

# Terraform CLI configuration overview

You can configure the Terraform CLI in global settings, which are separate
from any Terraform configuration and which apply across all working directories.

The default behavior of the Terraform CLI is suitable in most cases. As a result,
most of the global settings relate to advanced or automated workflows, or
unusual environmental conditions, such as running Terraform on an air-gapped
instance.

- The [CLI config file](/terraform/cli/config/config-file) configures provider
  installation and security features.
- Several [environment variables](/terraform/cli/config/environment-variables) can
  configure Terraform's inputs and outputs; this includes some alternate ways to
  provide information that is usually passed on the command line or read from
  the state of the shell.