First,Business  Laptop Briefcase Bag, measure your laptop correctly. Ignore marketing labels like "15-inch"—manufacturers’ size claims often refer to screen diagonals, not actual body dimensions. Use a tape measure to get the laptop’s width, depth, and thickness (include rubber feet or protruding parts). For example, a "15.6-inch" laptop might have a 14.8-inch width and 10-inch depth, so you’d search for 15-inch waterproof  polyester laptop sleeve to find a snug fit with basic protection . For 12-inch 2-in-1 devices like the Surface Pro, focus on actual dimensions around 292×366mm when looking for 12-inch 2-in-1 tablet laptop sleeve .       Second, opt for a snug but not tight fit. A sleeve should be 0.2–0.5 inches larger than your laptop’s width and depth. This leaves space for easy insertion while preventing sliding. For slim 14-inch models like Lenovo Yoga Air 14, 14-inch slim laptop sleeve for Yoga series ensures a precise fit without excess bulk . For rugged protection needs, shockproof impact-resistant laptop sleeve uses materials like Poron XRD to absorb impacts, but still requires matching your device’s dimensions .     Third, consider extra features. If you carry chargers or documents, choose a sleeve with a pocket—try searching for laptop sleeve with small accessory pocket to balance storage and fit . For 13-inch MacBook Air/Pro, 13-inch laptop sleeve for MacBook Air/Pro often accounts for the devices’ slim profiles (add 0.2–0.3 inches to measurements) . For 16-inch MacBook Pro, 16-inch thin laptop sleeve with document pocket works for those needing to carry papers without compromising fit . For devices with thick cases, laptop sleeve for bulky protective case helps accommodate the extra 0.3–0.8 inches of bulk.​   By focusing on actual dimensions rather than screen size, you’ll find a sleeve that balances protection and portability. Common searches like 14-inch dual-shock laptop bag also align with this principle, as they prioritize fit for standard 14-inch body sizes .​