Keen Seek Trail Runner vs On Running Cloudultra 3
Weight and specs compared for 2026 — and which one to choose.
Trail runners with wide toe box and high cushioning for technical terrain.
Full details →Trail running shoe at 10.4 oz per shoe for hiking, updated 2026 model with enhanced stability
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Keen Seek Trail Runner vs On Running Cloudultra 3: which should you buy?
If saving weight is your priority, the On Running Cloudultra 3 wins — at 295 g it is 12 g (4%) lighter than the Keen Seek Trail Runner (307 g). That said, the heavier option may justify the extra grams with more capacity, durability or comfort, so weigh the trade-off against how you'll use it.
See where both rank against everything else in this category on the lightest footwear page, or browse the full gear weight database.