Drag a letter sideways (or focus it and use the arrow keys) until the white space between letters looks even. Then lock it in and see where an ink-measuring ruler says the gaps should be. Doing nothing leaves every word badly off, so how close can you get?
Drag any letter except the first. Arrow keys nudge, Shift for bigger steps.
Your browser draws each letter to a hidden canvas. For every pixel row between the baseline and the capital height, the script measures the white space between the right edge of one letter and the left edge of the next, capped at 0.28 em so a big void above a lowercase letter does not count as a full gap. The average capped gap should match that of the pair HH set with the font's own default spacing. Where it does, the pair looks evenly spaced. This is optical kerning in a few lines, not a human typographer, so close calls are fair game. Scores use your own system serif font; units are thousandths of an em.