The price that matters is per clinical dose.
We compare supplements by the cost to take the amount actually studied in trials — every claim linked to its source, every label checked against the NIH database, no paid placement.
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Every supplement, ranked by what works.
Compare Magnesium Glycinate by Cost Per Day
Magnesium is our highest-traffic category — here's how the glycinate products we track compare right now.
| Product | Dose/Serving | Servings | Price | Cost/Day | Certification | Buy |
|---|---|---|---|---|---|---|
| BulkSupplements Magnesium Glycinate Powder Budget Pick | 225mg | 200 | $19.97 | $0.18 | None | Buy on Amazon |
| Vitamin Shoppe Magnesium Glycinate 400mg Best Value | 400mg | 90 | $19.99 | $0.23 | None | Buy on Amazon |
| Nature Made Magnesium Glycinate 200mg Quality Pick | 200mg | 60 | $11.20 | $0.36 | USP Verified | Buy on Amazon |
| Doctor's Best High Absorption Magnesium | 200mg | 60 | $13.99 | $0.46 | None | Buy on Amazon |
| KAL Magnesium Glycinate 400 | 400mg | 45 | $24.79 | $0.55 | None | Buy on Amazon |
| Thorne Magnesium Bisglycinate | 200mg | 60 | $26.00 | $0.87 | NSF Certified for Sport | Buy on Amazon |
Popular guides.
What Supplements Should You Actually Take?
The four filters that narrow a shelf down to one or two products.
Best Magnesium Supplement
All forms ranked. Best value: $0.24/day.
Vitamin D Dosage Guide
42% of adults are deficient. D2 vs D3, K2 pairing, dosing.
PCOS Supplements
Evidence-ranked protocols for hormonal balance.
Supplements for Anxiety
GAD-7 reduction of 4.5 points within 2 weeks.
Statin CoQ10 Depletion
92M Americans on statins. CoQ10 reduced 16–54%.
Can't Sleep?
Magnesium glycinate: −17 min sleep onset (P=0.0006).
Most-researched guides.
Best Tongkat Ali Supplement
Ranked by eurycomanone standardization, studied dose, and cost.
Tongkat Ali Supplement Guide
Product data and specs for every listed brand.
Magnesium Dosage Guide
Exact doses by age, sex, and goal — plus the safe upper limit.
Best Creatine Monohydrate
Ranked by cost per 5g dose and Creapure purity.
Best Fish Oil Supplement
Ranked by cost per 2000mg EPA+DHA, the clinical dose.
Best Omega-3 for Triglycerides
The dose and EPA ratio the lipid evidence points to.
Best Collagen Supplement
Ranked by dose, peptide type, and cost per day.
Best Electrolyte Drinks
Ranked by real sodium per serving and third-party testing.
Ferrous Sulfate vs Bisglycinate
Which iron form is gentler on your stomach.
Original research.
Free tools.
Supplement Audit
Check what you're taking for form, dose, quality, and cost.
Supplement Lookup
Search 207,000+ verified labels from the NIH DSLD.
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Medication Depletion
See which nutrients your medications quietly deplete.
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Medical disclaimer: Educational health information based on published clinical research — not medical advice, and not a replacement for your physician. Always discuss supplement changes with your doctor, especially if you take medications or have a health condition. Methodology.
Affiliate disclosure: As an Amazon Associate I earn from qualifying purchases. Rankings are determined by cost per effective dose and clinical evidence, not affiliate commissions. Read our methodology.