Before any state can be called "happy," someone has to decide what happiness means in numbers. Researchers generally use two very different lenses, and understanding both makes every ranking you'll ever see easier to read.
The first lens is direct self-report, where people simply rate their own lives. The best-known version is the Cantril ladder, the question behind the Gallup World Poll and the global World Happiness Report. As Gallup explains, you're asked to picture a ladder with ten rungs, where the top represents the best possible life for you and the bottom the worst, then say which rung you're standing on today. Your answer becomes a snapshot of how you evaluate your own life, which researchers call subjective well-being.
That term has a clear meaning in the research world. A National Academies review of the field describes subjective well-being as covering both how you judge your life overall and how you actually feel day to day, the good moods and the bad. In other words, there's a difference between thinking your life is going well and feeling cheerful on a Tuesday afternoon, and good measurement tries to respect both.
The second lens is the composite index, and this is the one behind most "happiest states" headlines. Instead of relying on a single survey question, a composite blends self-reported satisfaction with objective data such as income, employment, physical health, and community life. It's less a pure happiness poll and more a portrait of the conditions that tend to surround a happy life.
WalletHub's ranking is a composite. According to WalletHub's methodology, it scores each state across 30 metrics grouped into three dimensions: Emotional and Physical Well-Being, which carries the most weight at 50 points, plus Work Environment and Community and Environment at 25 points each. Some measures count far more than others, with the adult depression rate weighted especially heavily and serious outcomes like the suicide rate close behind. Every metric is graded on a 100-point scale, then combined into a single weighted score.
Keep this distinction in your back pocket as you read the countdown. A high rank reflects a favorable mix of conditions, not a guarantee that residents feel happier minute to minute. It's the difference between a state being a good setting for well-being and every person in it being content.