Functional template functions

These template functions help with control flow, conditional logic, and general utility operations. They let you make decisions, transform values, and work with data in flexible ways.

Home Assistant extends the Jinja2 template engine with many custom functions, filters, and tests. Each function on this page has its own page with detailed descriptions, parameters, and practical examples.

New to templates? Start with the templating documentation to learn the basics.

• Call a function dynamically apply Calls a function with a value, letting you pass any function into places where a filter is expected.
• Turn a macro into a function as_function Turns a template macro into a reusable function you can pass to map, select, and reject.
• Check if value another contains Tests if a value contains another value. Works with strings, lists, and dictionaries.
• Cycle through values cycler Creates an object that cycles through a list of values. Useful for alternating between values in a loop.
• Create a ionary dict Creates a dictionary from keyword arguments.
• Immediate if (ternary) iif Shorthand for basic if/else logic in a single expression.
• Join loop iterations joiner Creates a helper that joins loop iterations with a separator, returning an empty string on the first call.
• Generate placeholder text lipsum Generates lorem ipsum placeholder text. Useful for testing and prototyping templates.
• Create a mutable namespace Creates a mutable namespace object for storing variables across loop scopes in templates.
• Unicode code point ord Returns the Unicode code point for a single character.
• Choose a value random Chooses a random value from a list. Returns a different value each time the template is evaluated.
• Generate a number sequence range Generates a sequence of numbers, like Python's range(). Commonly used for looping a specific number of times.
• Parse a string version Converts a string into a version object that supports comparison operators.
• Combine iterables zip Zips multiple iterables together into a list of tuples, pairing elements by position.