Consumer Reports

The Fiskars X11 axe is great at splitting firewood, especially given its compact size. The Norden N12 Splitting Axe is better, primarily because it's longer and gives you more leverage. They share a blade design, complete with a wedged head, convex cheeks, a low friction finish, and a molded head-to-handle connection meant to protect from overstrikes. The N12 feels lively in our hands as we work through the woodpile, splitting rounds into fireplace-ready stacks. It also serves well for smaller tasks like kindling and larger ones like bucking up logs. It has enough heft and length to put weight behind your swings. 
We don't find the same precision in our strikes as the Gransfors affords, though. And, all of our testers preferred other options when it came to delicate or overhead work like limbing trees. Fiskars advertises the Norden as a one or two-handed axe. Our smallest woman tester definitely needed two. The head feels heavy, and we found it less balanced than the other two Fiskars options. We wouldn't use it to replace a machete or a dedicated splitting axe or maul with a longer handle. We do use it as a solid, all-around camping axe. If you're a van lifer, car camper, or don't mind some extra weight, this is a great option for your kindling chopping, firewood splitting, and log clearing needs.

OutdoorGearLab

The Fiskars X11 axe is great at splitting firewood, especially given its compact size. The Fiskars Norden N12 is better, primarily because it's longer and gives you more leverage. They share a blade design, complete with a wedged head, convex cheeks, a low friction finish, and a molded head-to-handle connection meant to protect from overstrikes. The N12 feels lively in our hands as we work through the woodpile, splitting rounds into fireplace-ready stacks. It also serves well for smaller tasks like kindling and larger ones like bucking up logs. It has enough heft and length to put weight behind your swings. 
We don't find the same precision in our strikes as the Gransfors affords, though. And, all of our testers preferred other options when it came to delicate or overhead work like limbing trees. Fiskars advertises the Norden as a one or two-handed axe. Our smallest woman tester definitely needed two. The head feels heavy, and we found it less balanced than the other two Fiskars options. We wouldn't use it to replace a machete or a dedicated splitting axe or maul with a longer handle. We do use it as a solid, all-around camping axe. If you're a van lifer, car camper, or don't mind some extra weight, this is a great option for your kindling chopping, firewood splitting, and log clearing needs.

Splitting Axe Comparison