Terraform Variables and tfvars Explained: Complete Beginner Guide

Terraform Variables and tfvars Explained#

Learn input variables, default values, types, validation, sensitive variables, terraform.tfvars , environment-specific values, and common mistakes.

What are Terraform variables?#

Variables make Terraform configuration reusable. Instead of hardcoding values, you define inputs and pass values for each environment.

Basic variable#

variable "region" { type = string description = "Cloud region" default = "ap-south-1" }

Using a variable#

provider "aws" { region = var.region }

terraform.tfvars#

region = "ap-south-1" environment = "dev"

Variable types#

• string
• number
• bool
• list(string)
• map(string)
• object({...})

Sensitive variables#

variable "db_password" { type = string sensitive = true }

Best practices#

• Use clear variable names.
• Add descriptions.
• Use types for validation.
• Use separate tfvars files for environments.
• Do not commit production secrets.

Related guides#

• Terraform Learning Path
• Terraform IaC Introduction