Independent supplement ratingsUS and Canada · Updated weekly
A ratings desk for a category that has spent thirty years grading its own homework.
A ratings desk for a category that has spent thirty years grading its own homework.
Capsules · 90 servings
600mg KSM-66 / 300–600mg studied
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The category's best-evidenced pick, done properly. This is KSM-66 — the ashwagandha extract with the most human research behind it — at 300 mg per capsule, so 600 mg at the two-capsule dose used in trials, from a brand that lab-tests obsessively and sells it for about $0.30 a serving. Ashwagandha is one of the few supplements on this whole site with genuine randomised-trial support for stress and sleep, and this is the cleanest way to take the exact thing that was studied.
A named, standardized extract (KSM-66), dose printed, no blend and no filler story. The research on ashwagandha for stress runs on standardized extracts like this at roughly 300–600 mg a day — which is exactly what you get here. Raw root powder at a bigger milligram number is not the same thing, which is why it scores below this.
Anyone who wants ashwagandha for stress, sleep or training recovery and wants the version that matches the studies. It's also effectively the value pick, even though it isn't the very cheapest — you're paying for the right extract, properly tested.
Reviewed and fact-checked by the NFS editorial team · Last updated 12 Jul 2026