Generated by SassMeister.com.

SassMeister-input.scss

// ----
// Sass (v3.4.12)
// Compass (v1.0.3)
// ----

@function convert($value, $currentUnit, $convertUnit){
  @if $currentUnit == px{
    
    @if $convertUnit == ems{
      @return $value / 16+em;
    }
    @else if $convertUnit == percent{
      @return percentage($value / 16);
    }
  
  }@else if $currentUnit == ems{
   
    @if $convertUnit == px{
      @return $value * 16+px;
    }
    @else if $convertUnit == percent{
       @return percentage($value);
    }
  
  }@else if $currentUnit == percent{
  
    @if $convertUnit == px{
      @return $value * 16 / 100+px;
    }
    @else if $convertUnit == ems{
      @return $value / 100+em;
    }
 
  }@else if $currentUnit == pts{
   
    @if $convertUnit == px{
      @return $value * 1.3333+px;
    }
    @else if $convertUnit == ems{
      @return $value / 12+em;
    }
    @else if $convertUnit == percent{
        @return percentage($value / 12)
    }
  }
}

.example1{
  font-size: convert(18, px, percent); /* converted from pixels */
}

.example2{
  font-size: convert(13, pts, ems); /* converted from points */
}

.example3{
  font-size: convert(2.5, ems, px); /* converted from ems */
}

.example4{
  font-size: convert(234, percent, px); /* converted from percentage */
}

SassMeister-output.css

.example1 {
  font-size: 112.5%;
  /* converted from pixels */
}

.example2 {
  font-size: 1.08333em;
  /* converted from points */
}

.example3 {
  font-size: 40px;
  /* converted from ems */
}

.example4 {
  font-size: 37.44px;
  /* converted from percentage */
}