How do you tell if a shirt fits without trying it on?

To determine if a shirt fits without trying it on, check the size label and compare it to your own measurements, focusing on chest, waist, and shoulder dimensions. Look for specific features like the cut (tailored, relaxed, or oversized) and fabric stretch, which can affect fit. Additionally, consider the shirt's length and sleeve size to ensure they align with your preferences. Lastly, read customer reviews for insights on sizing accuracy and overall fit.