How to choose the right size to fit your laptop well:A. If you have a MacBook:
1. Snug, tailored fit, offers precise protection. You can hold your MacBook with hard case or not. All form-fitting:
MacBook Air 13-inch (2012-2017 all Models, such as A1466/A1369)
MacBook Pro 13-inch without Retina (2012 Models and earlier, such as A1278)
2. Fine fit, and if you want to hold your MacBook with a hard case, it would be more perfect:
MacBook Pro 13-inch Retina (2012-2015 Models, such as A1425/A1502)
3. Big enough to hold the MacBook with hard case, slightly loose-fitting, NOT snug fit:
MacBook Pro 13-inch with or without Touch Bar(2016 Models and later, A1706/A1708)B. If you have the Dell, HP, Lenovo, ThinkPad, Samsung, Acer, Asus, Toshiba, iPad, Surface Pro, Surface Laptop etc:
Dell: Dell Inspiron 13 /Latitude 13 /Latitude D630 /Inspiron 13 7000 Series ,etc.
HP: HP Spectre x360 13 / Stream 13 /Spectre 13 / ENVY 13/ProBook 430 /Pavilion x360 13 /Envy x360 13 ,etc.
Lenovo: Lenovo Yoga 720/ Yoga 900 ,etc.
Asus: Asus Q304UA/ C300MA/ ZenBook UX330UA/UX303UA/UX303UB/ ZenBook Flip UX360CA/UX360UA/UX370UA/ Zenbook UX305/UX303/306 ,etc.
Acer: Acer Spin 5 /Chromebook R 13 /Aspire R 13, S5-371 /CB5-311 /Aspire V3-371 ,etc.
SAMSUNG: SAMSUNG Notebook 9 /Notebook 9 spin /Notebook 7 spin /Chromebook 2 /ATIV Book 9 Plus /ATIV Book 9 Lite /Notebook 9 Lite ,etc.
Toshiba: Toshiba Chromebook 2 /N2840/CB35-A3120/Z30-C1320 ,etc.
Please choose the correct size according to your Laptop's Dimensions rather than your Laptop/Tablet's Screen Size. And make sure your laptop's dimensions are smaller than the Internal Dimensions [13.39" x 9.45" x 0.79"], the more similar, the more perfect!