# Terraform Built-in Functions > Terraform functions perform specific tasks on configuration data: numeric, string, collection, date and time, file system and more. - Source: https://www.itwonderlab.com/terraform-functions/ - Published: 2023-12-18 - Updated: 2026-10-05 - Author: Javier Ruiz Jiménez (https://www.javierruizjimenez.com/) - Site: IT Wonder Lab (https://www.itwonderlab.com/) --- [Terraform functions](https://developer.hashicorp.com/terraform/language/functions) perform specific tasks on the data within the configuration files. OpenTofu has the same functions and a few more (see the [OpenTofu functions](https://opentofu.org/docs/language/functions/)). Try them with `terraform console` or `tofu console`, as shown in [Terraform Tools](https://www.itwonderlab.com/aws-terraform-tutorial-terraform-tools/). The functions `list` and `map` of older Terraform versions were removed: use `tolist` and `tomap`, or the literal syntax `[ ]` and `{ }`. ### Numeric Functions Perform mathematical operations like calculations, comparisons, and conversions on numbers. - **abs:** Calculate absolute value. - **ceil:** Round up to the nearest integer. - **floor:** Round down to the nearest integer. - **log:** Compute the logarithm of a number in a given base. - **max:** Return the largest of the given numbers (use `...` to expand a list). - **min:** Return the smallest of the given numbers (use `...` to expand a list). - **parseint:** Parse a string as an integer in a given base. - **pow:** Raise a number to a power. - **signum:** Determine the sign of a number (-1, 0, or 1). ### String Functions Manipulate text data, including formatting, searching, and transformations. - **chomp:** Remove trailing newline characters. - **endswith:** Check if a string ends with a specific substring. - **format:** Apply formatting placeholders to a string. - **formatlist:** Produce a list of strings by formatting each element of the given lists. - **indent:** Add whitespace indentation to a string. - **join:** Combine strings into a single string with a separator. - **lower:** Convert all characters to lowercase. - **regex:** Perform regular expression matching and extraction. - **regexall:** Find all occurrences of a regular expression pattern. - **replace:** Substitute one substring with another within a string. - **split:** Divide a string into a list of substrings based on a delimiter. - **startswith:** Check if a string starts with a specific substring. - **strcontains:** Check if a substring is present within a string. - **strrev:** Reverse the order of characters in a string. - **substr:** Extract a specific substring from a string. - **title:** Capitalize the first letter of each word in a string. - **trim:** Remove the specified characters from the start and the end of a string. - **trimprefix:** Remove a specific prefix from a string. - **trimsuffix:** Remove a specific suffix from a string. - **trimspace:** Remove leading and trailing whitespace from a string. - **upper:** Convert all characters to uppercase. ### Collection Functions Work with lists and maps, performing tasks like filtering, sorting, and aggregation. - **alltrue:** Check if all elements in a list are true. - **anytrue:** Check if any element in a list is true. - **chunklist:** Divide a list into sublists of a specified size. - **coalesce:** Return the first argument that is neither null nor an empty string. - **coalescelist:** Return the first list that is not empty. - **compact:** Remove empty strings from a list of strings. - **concat:** Combine two or more lists into a single list (use `merge` for maps). - **contains:** Check if a list contains a specific element. - **distinct:** Remove duplicate elements from a list. - **element:** Access a specific element within a list by index. - **flatten:** Merge sublists within a list into a single, flat list. - **index:** Find the position of an element within a list. - **keys:** Extract the keys from a map. - **length:** Get the number of elements in a list, map or set, or the length of a string. - **lookup:** Access a specific value within a map by key. - **matchkeys:** Select the values of a list by matching a second list of keys against a list of allowed keys. - **merge:** Combine multiple maps into a single map, overriding conflicting keys. - **one:** Extract the only element from a list, ensuring its length is 1. - **range:** Generate a list of numbers in a specified range. - **reverse:** Reverse the order of elements in a list. - **setintersection:** Find the common elements between multiple sets. - **setproduct:** Combine multiple sets by Cartesian product. - **setsubtract:** Remove elements from one set that are present in another. - **setunion:** Combine multiple sets into a single set, removing duplicates. - **slice:** Extract a sublist from a list based on specific indices. - **sort:** Sort a list of strings in lexicographical order. - **sum:** Calculate the sum of all numeric elements in a list. - **transpose:** Swap the keys and the values of a map of lists of strings. - **values:** Extract the values from a map. - **zipmap:** Combine two lists into a map, pairing elements at corresponding indices. ### Encoding Functions Encode and decode data in different formats like base64, JSON, and YAML. - **base64decode:** Decode base64-encoded data. - **base64encode:** Encode data in base64 format. - **base64gzip:** Compress and encode data with base64. - **csvdecode:** Decode comma-separated values (CSV) data into a list of maps. - **jsondecode:** Decode a JSON string into a value (object, list or primitive). - **jsonencode:** Encode any value as a JSON string. - **textdecodebase64:** Decode base64-encoded text data. - **textencodebase64:** Encode text data in base64 format. - **urlencode:** Encode a string for safe inclusion in URLs. - **yamldecode:** Decode a YAML string into a value. - **yamlencode:** Encode any value as a YAML string. ### File System Functions Interact with files and directories, reading contents, checking existence, and manipulating paths. - **abspath:** Get the absolute path of a file based on the current working directory. - **dirname:** Extract the directory part of a file path. - **pathexpand:** Expand a leading tilde (~) in a file path to the home directory of the current user. - **basename:** Extract the last element of a file path (the file name, including its extension). - **file:** Read the contents of a file as a string. - **fileexists:** Check if a file exists at a specific path. - **fileset:** Enumerate files within a directory based on patterns and glob. - **filebase64:** Encode the contents of a file in base64 format. - **templatefile:** Render a template file with embedded variables and interpolation. ### Date and Time Functions Work with timestamps and dates, formatting them, adding durations, and comparing them. - **formatdate:** Convert a timestamp to a string in a specific format. - **plantimestamp:** Get the timestamp of the current Terraform plan execution. - **timeadd:** Add a duration to a timestamp or time string. - **timecmp:** Compare two timestamps or time strings for chronological order. - **timestamp:** Return the current UTC date and time in RFC 3339 format. ### Hash and Crypto Functions Generate secure hashes and cryptographic operations for data security. - **base64sha256:** Generate a base64-encoded SHA-256 hash of data. - **base64sha512:** Generate a base64-encoded SHA-512 hash of data. - **bcrypt:** Generate a password hash using bcrypt algorithm. - **filebase64sha256:** Calculate the base64-encoded SHA-256 hash of a file’s contents. - **filebase64sha512:** Calculate the base64-encoded SHA-512 hash of a file’s contents. - **filemd5:** Generate an MD5 hash of a file’s contents. - **filesha1:** Generate an SHA-1 hash of a file’s contents. - **filesha256:** Generate an SHA-256 hash of a file’s contents. - **filesha512:** Generate an SHA-512 hash of a file’s contents. - **md5:** Generate an MD5 hash of data. - **rsadecrypt:** Decrypt data using RSA private key. - **sha1:** Generate an SHA-1 hash of data. - **sha256:** Generate an SHA-256 hash of data. - **sha512:** Generate an SHA-512 hash of data. - **uuid:** Generate a universally unique identifier (UUID). - **uuidv5:** Generate a UUID based on a namespace and name. ### IP Network Functions Work with CIDR blocks, extracting addresses, netmasks, and generating subnets. - **cidrhost:** Calculate a full host IP address for a given host number within a CIDR block. - **cidrnetmask:** Extract the netmask from a CIDR block. - **cidrsubnet:** Divide a CIDR block into multiple subnets of a specified size. - **cidrsubnets:** Calculate a sequence of consecutive subnets within a CIDR block. ### Type Conversion Convert values between different data types like strings, numbers, and maps. - **can:** Evaluate an expression and return true if it produces no error. - **nonsensitive:** Remove the sensitive mark from a value, so it can be shown in the output. - **sensitive:** Mark a value as sensitive, so it is hidden in the plan and in the output. - **tobool:** Convert a value to a boolean (true or false). - **tolist:** Convert a value to a list. - **tomap:** Convert a value to a map. - **tonumber:** Convert a value to a number. - **toset:** Convert a value to a set. - **tostring:** Convert a value to a string. - **try:** Evaluate the expressions in order and return the result of the first one that does not produce an error. - **type:** Return the type of a value (only available in `terraform console`).