Top Picks
These are the products we currently recommend, chosen from what we have reviewed across the site. Each pick lists what it is good for and who it suits, so you can match one to your situation rather than defaulting to the cheapest listing.
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A practitioner-channel brand rather than a mass-market one, and it doses differently on purpose: 50 mg (1,000 FU) per capsule, taken one capsule three times daily before meals, so enzyme activity is spread across the day instead of arriving in a single 4,000 FU hit. The listing is a two-pack, 180 capsules in total. Pick it if you specifically want divided dosing or your practitioner asked for this brand. If you just want the standard once-daily serving, the higher-potency options are simpler.
Double Wood’s label is unusually specific about what you are actually getting: each capsule carries 100 mg standardised to 2,000 FU, which is the daily dose the largest randomised circulation trials actually used, so the two-capsule serving is double what those trials tested. The 120-count bottle is about two months at that serving. Third-party tested, vegetarian, non-GMO and gluten-free. Because the enzyme is fermented from Japanese natto, the label carries a trace-soy warning that matters if you react to soy.
The same formula as the 120-count bottle at double the size: 100 mg and 2,000 FU per capsule, 120 two-capsule servings, roughly four months at 4,000 FU a day. Nattokinase is something people take continuously rather than in short courses, so the larger bottle is usually the cheaper way per serving to stay on it. Same third-party testing, vegetarian capsule and trace-soy warning as the smaller size.
The plainest entry point on this list: one veggie capsule delivers 100 mg standardised to 2,000 FU, with no blend and nothing else added, 90 capsules to a bottle. Non-GMO, gluten-free, third-party tested and made to GMP standards in the USA. This is the one to pick if you are trying nattokinase for the first time and want to see how you tolerate a single-capsule dose before committing to a full 4,000 FU serving.
NOW’s larger 120-capsule size at 100 mg per VegiCap. NOW manufactures in an NPA A-rated GMP-certified facility, which means the stability and potency testing side of production is externally audited rather than self-declared, and that is the main reason to pay above the cheapest listing. The bigger count suits someone already settled into a daily routine and re-ordering rather than experimenting.
Not a plain nattokinase product, and worth being clear about that before you buy. Serracor-NK is a systemic enzyme blend pairing acid-resistant serrapeptase with acid-resistant nattokinase, plus CoQ10, magnesium and a herbal base, in a 300-capsule bottle. Choose it only if you specifically want the serrapeptase combination. If you are trying to work out what nattokinase on its own does for you, a single-ingredient product makes that far easier to judge.