Variables & Expressions

Variables

Output variables using double curly braces:

{{ name }}
{{ user.email }}
{{ items[0] }}

Property Access

Dot Notation

{{ user.name }}
{{ user.profile.avatar }}
{{ user.settings.theme }}

Bracket Notation

{{ data['key'] }}
{{ data["key with spaces"] }}
{{ items[0] }}

Array Index (Django-style)

{{ items.0 }}
{{ items.1 }}
{{ matrix.0.0 }}

Filters

Apply filters with the pipe character:

{{ name|upper }}
{{ text|truncatechars:20 }}
{{ price|floatformat:2 }}

Filter Chaining

{{ name|lower|capitalize|truncatechars:30 }}
{{ items|sort|reverse|join:", " }}

Filter Arguments

Django-style (colon):

{{ text|truncatechars:20 }}
{{ text|replace:"old","new" }}

Jinja2-style (parentheses):

{{ text|truncate(20) }}
{{ text|replace("old", "new") }}

Operators

Comparison

Operator	Description
==	Equal
!=	Not equal
<	Less than
>	Greater than
<=	Less than or equal
>=	Greater than or equal

{% if age >= 18 %}Adult{% endif %}
{% if status == "active" %}Active{% endif %}
{% if count != 0 %}Has items{% endif %}

Logical

Operator	Description
and	Logical AND
or	Logical OR
not	Logical NOT

{% if user and user.is_admin %}Admin{% endif %}
{% if is_staff or is_admin %}Has access{% endif %}
{% if not is_banned %}Welcome{% endif %}

Membership

{% if "admin" in user.roles %}Admin{% endif %}
{% if key in data %}Key exists{% endif %}

String Concatenation

{{ "Hello, " ~ name ~ "!" }}
{{ first_name ~ " " ~ last_name }}

Math

{{ price * quantity }}
{{ total + tax }}
{{ count / 2 }}
{{ remainder % 10 }}

Ternary Expressions

Jinja2-style conditional expressions:

{{ "Active" if is_active else "Inactive" }}
{{ user.name if user else "Guest" }}
{{ count if count > 0 else "None" }}

Tests (is operator)

Check values with the is operator:

{% if value is defined %}Defined{% endif %}
{% if num is even %}Even{% endif %}
{% if items is empty %}No items{% endif %}
{% if count is divisibleby(3) %}Divisible by 3{% endif %}

See Built-in Tests for all available tests.

Undefined Variables

Undefined variables output empty string by default:

{{ undefined_var }}  {# Outputs nothing #}

Use default filter for fallback:

{{ name|default:"Anonymous" }}
{{ count|default:0 }}

Context Lookup Order

Variables are resolved in this order:

1. Local scope (set/with blocks)
2. Loop variables
3. Template context
4. Global variables

{% set name = "Local" %}
{% for name in names %}
  {{ name }}  {# Loop variable #}
{% endfor %}
{{ name }}  {# Local variable #}