What angle should I sharpen kitchen knives at?

Most Western chef's knives (Wüsthof, Henckels, Victorinox) are designed for roughly a 20-degree-per-side edge, while Japanese-style knives are typically 15 degrees per side. Several of the top picks here, including the Chef's Choice 15XV and adjustable guided systems, target the 15-degree bevel that mainstream reviewers and r/chefknives users say produces a noticeably keener edge on most modern kitchen knives.