What size pack do I need for multi-day backpacking?

For trips of two to five nights, most reviewers gravitate toward 50–65L; 65L is the most common all-rounder. Longer expeditions, bulky cold-weather gear, or carrying group equipment push shoppers toward 75L and up. Verified-purchase reviewers consistently note that an oversized pack tempts you to overpack, so match capacity to your actual trip length.