Molang

What Is Molang? ​

Molang is a math-based expression language used throughout Minecraft Bedrock Edition. It is used in animations, particles, render controllers, and behavior logic.

Expressions ​

Molang expressions are like little math problems the game solves constantly.

q.health < 5 ? 1 : 0

This returns 1.0 if health is less than 5, otherwise 0.0.

Accessing Game Data ​

1. Queries (query. or q.) ​

Read-only values provided by the game. ​

Queries can either return a value directly, or accept arguments to return context-specific results.

Examples without arguments:

• query.is_sneaking
• query.time_of_day
• query.health

Examples with arguments:

• query.position(0)
• query.is_item_name_any('slot.weapon.offhand', 'minecraft:dirt')
• query.in_range(5, 0, 10)

2. Variables (variable. or v.) ​

Read-write values stored per-entity. ​

Examples:

• variable.buff_timer
• variable.has_effect

v.buff_timer = (v.buff_timer ?? 0) + q.delta_time;

Default Variables ​

3. Temporary Variables (temp. or t.) ​

Read-write values stored per-pack. ​

t.temp_speed = q.ground_speed * 1.2;

Temporary variables are pack-scoped and ephemeral. They only exist for the duration of the current Molang expression or loop. They are shared globally across a pack and are cleared automatically after each expression completes. They do not support structs (no .x, .y, .z).

4. Context Variables (context. or c.) ​

Read-only values from the base game in specific situations. ​

Common Context Variables ​

Example:

context.other->query.remaining_durability

Logic and Conditions ​

Comparison Operators ​

q.health <= 10

Boolean Logic ​

q.is_sneaking && q.is_using_item

Conditional Operators ​

Use ? and : like if-else:

• Binary: condition ? result
• Ternary: condition ? true : false

q.is_jumping ? 3 : 0

You can also use the null coalescing operator (??) to provide a fallback when a variable might not be initialized:

• fallback = value ?? default

v.timer = (v.timer ?? 0) + q.delta_time

This avoids content log errors if v.timer has not been defined yet.

Math Functions ​

Molang supports a wide range of math functions, using degrees (not radians) for trigonometry. These are useful for animation timing, oscillation, directional math, clamping, and more.

Structs ​

Structs in Molang are values that contain multiple related fields, like .x, .y, .z.

You can create your own structs using variable. and assign values to their fields directly:

v.location.x = 1;
v.location.y = 2;
v.location.z = 3;

These values can then be reused or passed to other expressions:

v.target = v.other_mob->v.location;

Loops and Flow Control ​

You can run expressions multiple times using loop.

v.a = 1;
v.b = 1;

loop(10, {
    t.next = v.a + v.b;
    v.a = v.b;
    v.b = t.next;
});

break and continue ​

• break; exits the current loop early
• continue; skips to the next iteration

loop(10, {
    (v.a > 5) ? break;
    v.a += 1;
});

Simple vs Complex Expressions ​

• Simple: a single expression that returns a value

math.sin(q.anim_time * 10)

• Complex: multiple statements with ; and an explicit return

t.a = math.sin(q.anim_time * 10);
t.b = t.a * t.a;
return t.b + 1;

Versioning and min_engine_version ​

Molang behavior can change depending on the min_engine_version defined in your pack’s manifest.json. These changes improve how expressions behave, fix bugs, and deprecate older behavior.

Make sure your pack's engine version is set correctly to take advantage of the latest fixes and syntax improvements.