What fill power should I look for in a down pillow?

Fill power measures loft per ounce of down; higher numbers mean fluffier, lighter, longer-lasting fill. 600–700 fill power is solid mid-range, 800+ is considered premium, and 900 fill power (found in a few luxury pillows) is the top tier. Specialist bedding subreddits consistently note that fill power matters more than total weight when judging quality.