Generated by SassMeister.com.

SassMeister-input-HTML.html

<div class="test">test headline</div>

SassMeister-input.scss

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

@mixin textScaling ($minSize, $maxSize, $minWidth) {
  $scalingFactor: $minSize/$minWidth;
  font-size: $minSize;
  @media (min-width: $minWidth) {
    font-size: ($scalingFactor*100)+vw
  }
  @media (min-width: ($maxSize/$scalingFactor)) {
    font-size: $maxSize;
  }
  
}

.test {
  @include textScaling (28px, 52px, 800px);
}

SassMeister-output.css

.test {
  font-size: 28px;
}
@media (min-width: 800px) {
  .test {
    font-size: 3.5vw;
  }
}
@media (min-width: 1485.71429px) {
  .test {
    font-size: 52px;
  }
}

SassMeister-rendered.html

<div class="test">test headline</div>