JSFiddle - React, Tailwind, and code Playground

HTML

<div>
  <p class="truncated calculated-width">
    This long line of text should be truncated.
  </p>
</div>

CSS

.truncated {
  text-overflow: ellipsis;
  white-space: nowrap;
  overflow: hidden;
}

.calculated-width {
  width: calc(20%);
}