![Magnesium 400mg [High Potency] Supplement](https://m.media-amazon.com/images/I/61tsdnhqtBL._AC_SL500_.jpg)
Magnesium 400mg [High Potency] Supplement
- Magnesium
- Tablet
- 120
- Immune Support
- More reviewed than 69%
A standard magnesium oxide tablet that covers the basics at a lower cost than chelated forms, reasonable for general use rather than absorption-sensitive supplementation.
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How it ranks among the 108 magnesium we track
4.6★ across 8,100 Amazon ratings, Bayesian-smoothed toward the category average.
8,100 Amazon ratings, weighted on a log scale so huge counts don't drown everything.
10,000+ bought on Amazon last month.
Brand identity, imagery, description and spec coverage.
The ProductDome score is separate from the Amazon rating shown above: it combines the Bayesian-smoothed Amazon rating with evidence volume, tracked demand, and data quality across the 108 magnesium we track - how the scorecard works · full magnesium data report. Confidence: high - strong rating volume and complete data.Last refreshed Aug 4, 2026. Data-computed, not a hands-on test. Compiled by the ProductDome Research Team.
Overview
This 120-tablet magnesium oxide formula delivers 400mg magnesium per serving at high potency, positioned for immune support, muscle recovery, leg cramps and general relaxation.
Magnesium oxide is the least expensive and most common form on the market, but it also has lower bioavailability than glycinate or citrate, meaning a meaningful portion of the dose can pass through unabsorbed. At 120 tablets, this bottle covers roughly four months at one tablet daily.
- 400mg magnesium oxide per tablet
- 120 tablets per bottle
- Gluten free formula
- Marketed for immune and muscle recovery support
Who it's for
Budget-focused buyers who want a basic, no-frills magnesium oxide tablet rather than a specialty chelated form, and who don't need the higher absorption of glycinate.
Strengths and trade-offs
Drawn from this product's published specifications.
- 400mg high-potency magnesium oxide dose
- 120-tablet bottle lasts about four months
- Magnesium oxide has lower bioavailability than glycinate or citrate
- Can cause digestive upset in some people at this dose
Performance notes
Magnesium oxide carries a high elemental magnesium content per tablet but is absorbed less efficiently in the gut than chelated forms like glycinate or citrate, which is why some users notice a laxative effect at higher doses.
Specifications
| Brand | Magnesium |
|---|---|
| Model | 12 |
| Form | Tablet |
| Supplement Type | Calcium, Magnesium, Potassium |
| Count | 120 |
| Benefits | Immune Support |
| Flavor | Unflavored |
| Allergens | Gluten Free |
Other Magnesium magnesium
How it compares
This product against the closest alternatives we track in magnesium.
| Product | Amazon rating | Ratings | ProductDome score |
|---|---|---|---|
| Magnesium 400mg [High Potency] SupplementThis product | 4.6 / 5 | 8,100 | 4.6 / 5 |
| Nature Made Magnesium Oxide 250 mgNATURE | 4.7 / 5 | 34,500 | 4.6 / 5 |
| NaturalSlim MagicMag Magnesium Citrate Powder for StressNaturalSlim | 4.7 / 5 | 26,700 | 4.6 / 5 |
| NOW Supplements, Magnesium Citrate, Enzyme Function*, Nervous System Support*, 120 Veg…Now | 4.7 / 5 | 25,200 | 4.6 / 5 |
| Life Extension Magnesium CapsLife | 4.7 / 5 | 16,700 | 4.6 / 5 |
Similar magnesium from other brands
Questions about the Magnesium 12
Common buyer questions answered straight from the product spec data - no fluff, no "it depends".
What form of magnesium is in model 12?
It's magnesium oxide, dosed at 400mg per tablet.
How long does a 120-tablet bottle last at one a day?
About four months.
Is this magnesium tablet gluten free?
Yes, it's listed as gluten free.