glyph-widths.js

(function() {
  function range(start,stop) {
    var result=[];
    for (var idx=start.charCodeAt(0),end=stop.charCodeAt(0); idx <=end; ++idx){
      result.push(String.fromCharCode(idx));
    }
    return result;
  };

  let glyphWidths = {};

  range('!', '~').forEach((char) => {
    const e = document.createElement('span');
    e.style.fontSize = '13px';
    e.style.fontFamily = 'Camphor';
    e.innerHTML = char;
    document.body.appendChild(e);
    const width = e.offsetWidth;
    document.body.removeChild(e);
    glyphWidths[char] = width;
  });

  console.log(glyphWidths);

}());