How accurate are cost of living calculators when you factor in transit?

[Dennis40]

My partner and I are considering a move for work, and we're trying to compare potential cities. I've been looking at those cost of living by city calculators online, but they seem to give such a broad, averaged picture. For example, they might say a city is 20% more expensive, but does that factor in things like needing a car in one place versus having good public transit in another? How accurate are these tools for real, day-to-day budgeting?