SASS function to calculate needed units

calcSize.scss

@function strip-unit($num) {
	@return $num / ($num * 0 + 1);
}

@function calcSize($size,$base:16px,$unit:1rem,$calc:true) {
	// https://gist.github.com/MrSwed/958077f384bfeb62cc799b0946999590
	@if ($calc) {
		@return calc(#{$unit} * #{strip-unit($size)} / #{strip-unit($base)});
	} @else {
		@return $unit * $size / $base;
	}
	/* Examples
			font-size: calcSize(18px);                |    font-size: calc(1rem * 18 / 16);
			font-size: calcSize(14px,16px,1em,false); |    font-size: 0.875em;
		*/
}

@function calcEm($size,$base:16px,$unit:1em,$calc:false) {
	@return calcSize($size, $base, $unit, $calc);
}

@function calcRem($size,$base:16px,$unit:1rem,$calc:false) {
	@return calcSize($size, $base, $unit, $calc);
}