• <expression> < <expression> returns whether the first expression’s value is less than the second’s.
• <expression> <= <expression> returns whether the first expression’s value is less than or equal to the second’s.
• <expression> > <expression> returns whether the first expression’s value is greater than to the second’s.
• <expression> >= <expression>, returns whether the first expression’s value is greater than or equal to the second’s.

@debug 100 > 50; // true
@debug 10px < 17px; // true
@debug 96px >= 1in; // true
@debug 1000ms <= 1s; // true

@debug 100 > 50  // true
@debug 10px < 17px  // true
@debug 96px >= 1in  // true
@debug 1000ms <= 1s  // true

Unitless numbers can be compared with any number. They’re automatically converted to that number’s unit.

@debug 100 > 50px; // true
@debug 10px < 17; // true

@debug 100 > 50px  // true
@debug 10px < 17  // true

Numbers with incompatible units can’t be compared.

@debug 100px > 10s;
//     ^^^^^^^^^^^
// Error: Incompatible units px and s.

@debug 100px > 10s
//     ^^^^^^^^^^^
// Error: Incompatible units px and s.