“Optimize” or “Optimise”—Whats the difference? | Sapling “Optimize” or “Optimise” Language Optimize and optimise are both English terms Usage Optimize is predominantly used in 🇺🇸 American (US) English (en-US) while optimise is predominantly used in 🇬🇧 British English (used in UK AU NZ) (en-GB) In terms of actual appearance and usage, here's a breakdown by country, with usage level out of 100 (if available) 👇: