Magnesium oxide delivers the highest concentration of elemental magnesium per milligram of compound — roughly 60% by weight, compared to 10–15% for chelated forms like glycinate or taurate. This means oxide capsules can pack more elemental magnesium into fewer pills, and the products are typically the most affordable magnesium option on the market. The tradeoff is lower bioavailability: less of the magnesium is absorbed per dose compared to citrate or chelated forms. At higher doses, oxide also has an osmotic laxative effect. Labels for oxide products show both the elemental magnesium (what counts toward your daily intake) and the compound weight. This page compares products by elemental magnesium content. Products below are ranked by cost at your chosen daily dose.
Read our Magnesium Oxide price comparison guide for tips on what to look for when buying magnesium oxide.
| # | Product | 30-day cost | Supply | Sticker | |
|---|---|---|---|---|---|
| 1 |
NOW Supplements, Magnesium Oxide, Enzyme Function*, Nervous System Support*, 8-Ounce (Pack of 2)
NOW Foods Store
|
$0.65 | 658d | $19.80 | View on Amazon |
| 2 |
NOW Foods Supplements, Magnesium Oxide, Enzyme Function*, Nervous System Support*, 8-Ounce
NOW Foods Store
|
$0.65 | 329d | $9.90 | View on Amazon |
| 3 |
Best Naturals Pure Magnesium Oxide Powder 1 Pound
Best Naturals Store
|
$0.83 | 679d | $14.99 | View on Amazon |
| 4 |
Horbaach Magnesium Oxide Powder | 8 Ounce (227g) | 400 mg Per Serving | Vegetarian, Non-GMO & Gluten Free Supplement
Horbäach Store
|
$0.92 | 324d | $9.99 | View on Amazon |
| 5 |
Gade Nutrition Pure Magnesium Oxide Powder | Non-GMO, Gluten-Free, Filler Free, Highly Absorbable | USA Made
GADE NUTRITION BOOST YOUR HEALTH Store
|
$1.00 | 749d | $19.95 | View on Amazon |
| 6 |
Magnesium Oxide 400mg, 400 Capsules | High Purity Elemental Form – Extra Strength – Essential Mineral Supplements for Muscle, Digestion, Bone, & Heart Support – Non-GMO & No Gluten
NatureBell Store
|
$1.12 | 240d | $14.95 | View on Amazon |
| 7 |
Magnesium Oxide 400mg, 500 Capsules | Elemental Form for Max Concentration | Supports Calm, Muscle & Nerve Health | Non-GMO
Micro Ingredients Store
|
$1.14 | 300d | $18.99 | View on Amazon |
| 8 |
BulkSupplements.com Magnesium Oxide Powder - Magnesium Oxide Supplement, Mineral Supplement - Food Grade & Gluten Free, 835mg per Serving, 500g (1.1 lbs) (Pack of 1)
BulkSupplements Store
|
$1.20 | 749d | $23.97 | View on Amazon |
| 9 |
Vitamatic Magnesium Oxide Powder – 1000 mg Per Serving – 250 Servings – High Absorption Magnesium Supplement – 600 mg Elemental Magnesium – Unflavored
Vitamatic Store
|
$1.20 | 375d | $9.99 | View on Amazon |
| 10 |
Nature Made Magnesium Oxide 250 mg, Magnesium Supplements for Men and Women, Support for Muscle, Heart, Bone and Nerve Health, 100 Tablets, 100 Day Supply
Nature Made Store
|
$1.35 | 63d | $4.49 | View on Amazon |
| 11 |
Nutricost Magnesium Oxide 375mg, 240 Capsules - 210mg of Magnesium, Non-GMO, Gluten Free
Nutricost Store
|
$1.37 | 126d | $10.99 | View on Amazon |
| 12 |
Swanson Magnesium Bone & Muscle Health Support 200 Milligrams (2 Caps per 400 mg Serving Magnesium Oxide) 500 Capsules
Swanson Store
|
$1.37 | 250d | $11.39 | View on Amazon |
| 13 |
Rugby Magnesium Oxide 400 mg Tablets - Dietary Supplement - Gluten-Free - 120 Count (1 Pack)
RUGBY LABORATORIES Store
|
$1.50 | 72d | $6.00 | View on Amazon |
| 14 |
Magnesium 400mg [High Potency] Supplement – Magnesium Oxide for Immune Support, Muscle Recovery, Leg Cramps, Relaxation - 3 Pack | Total 360 Count
P Puregen Labs Store
|
$1.58 | 216d | $18.95 | View on Amazon |
| 15 |
Best Naturals Magnesium Oxide 500mg 360 Tablets - 1 Year Supply - Magnesium for Immune Support, Muscle Recovery, Leg Cramps, Relaxation
Best Naturals Store
|
$1.58 | 450d | $18.99 | View on Amazon |
| 16 |
Best Naturals Magnesium oxide 500 mg 180 tablets
Best Naturals Store
|
$1.67 | 225d | $9.99 | View on Amazon |
| 17 |
BulkSupplements.com Magnesium Oxide Powder - Magnesium Oxide Supplement, Mineral Supplement - Food Grade & Gluten Free, 835mg per Serving, 250g (8.8 oz) (Pack of 1)
BulkSupplements Store
|
$1.70 | 374d | $16.97 | View on Amazon |
| 18 |
Heivy Magnesium Oxide 400mg – Magnesium Supplement for Support Muscle Recovery & Relaxation - Vegan, Gluten-Free, Made in USA, 120 Tablets
Heivy Store
|
$1.75 | 120d | $6.99 | View on Amazon |
| 19 |
Carlyle Magnesium Oxide 500mg | 120 Capsules | Premium Quality | Non-GMO and Gluten Free Supplement
Carlyle Store
|
$1.87 | 150d | $7.49 | View on Amazon |
| 20 |
Nutricost Magnesium Oxide 750mg, 240 Capsules - 420mg of Magnesium, Non-GMO, Gluten Free
Nutricost Store
|
$1.87 | 252d | $14.95 | View on Amazon |
| 21 |
Horbäach Magnesium Oxide 865 mg | 200 Capsules | Non-GMO and Gluten Free Supplement
Horbäach Store
|
$1.95 | 250d | $12.99 | View on Amazon |
| 22 |
Magnesium 400mg [High Potency] Supplement – Magnesium Oxide for Immune Support, Muscle Recovery, Leg Cramps and Relaxation 120 Tablets
P Puregen Labs Store
|
$2.19 | 72d | $8.75 | View on Amazon |
| 23 |
PureFormulas Magnesium Oxide 300 mg – Healthy Heart, Relaxation, Immune Support, Non-GMO Vegetarian Capsules – 250 Count
PureFormulas Store
|
$2.40 | 188d | $19.99 | View on Amazon |
| 24 |
Douglas Laboratories Magnesium Oxide | Supports Normal Heart Function and Bone Formation* | 250 Capsules
Douglas Laboratories Store
|
$2.64 | 188d | $22.00 | View on Amazon |
| 25 |
BulkSupplements.com Magnesium Oxide Capsules - Magnesium Supplement, Magnesium Oxide 500mg - Gluten Free, 1 Capsule per Serving, 180 Count (Pack of 1)
BulkSupplements Store
|
$2.99 | 225d | $17.97 | View on Amazon |
| 26 |
Nature's Truth Magnesium Oxide 500mg Capsules | 90 Count | Non-GMO & Gluten Free High Strength Supplement
Nature's Truth Store
|
$3.00 | 113d | $8.99 | View on Amazon |
| 27 |
Carlyle Magnesium Oxide 400mg | 180 Softgels | Essential Mineral | Non-GMO and Gluten Free Supplement
Carlyle Store
|
$3.00 | 180d | $17.99 | View on Amazon |
| 28 |
Piping Rock Magnesium Softgels | 400 mg | 150 Count | Magnesium Oxide Supplement | Non-GMO, Gluten Free
Piping Rock Store
|
$3.15 | 150d | $15.74 | View on Amazon |
| 29 |
Amazing Formulas Magnesium Oxide Supplement | 500 Mg per Serving | 90 Capsules | Non-GMO | Gluten-Free | Made in USA
Amazing Nutrition Store
|
$3.33 | 113d | $9.99 | View on Amazon |
| 30 |
Pure Original Ingredients Magnesium Oxide No Magnesium Or Rice Fillers, Always Pure, Lab Verified (365 Capsules)
PURE ORIGINAL INGREDIENTS
|
$3.62 | 207d | $21.99 | View on Amazon |
| 31 |
GeriCare Magnesium Oxide Supplement 240 mg of Elemental Magnesium, 120 Tablets, Essential Mineral Support, Promotes Vascular Health, Bone Strength, and Muscle Function (Pack of 1)
GeriCare Store
|
$4.00 | 72d | $7.99 | View on Amazon |
| 32 |
Product gallery
Nature's Truth Store
|
$4.16 | 72d | $9.99 | View on Amazon |
| 33 |
MD. Life Magnesium Oxide 400mg Capsules - High Absorption Magnesium Supplement for Leg Cramps, Sleep & Vascular Health - 90 Capsules - Non-GMO Pills for Women
MD.LIFE Store
|
$5.05 | 90d | $15.15 | View on Amazon |
| 34 |
Sports Research® Magnesium Oxide 420mg with Coconut MCT Oil - Magnesium Supplement for Muscle, Nerve, and Bone Support* - Gluten-Free, Non-GMO - 90 Softgels
|
$5.32 | 95d | $15.95 | View on Amazon |
| 35 |
Pure Original Ingredients Magnesium Oxide, (100 Capsules) Always Pure, No Additives Or Fillers, Lab Verified
PURE ORIGINAL INGREDIENTS
|
$5.99 | 57d | $9.99 | View on Amazon |
| 36 |
MD. Life Magnesium Oxide 400mg Capsules - High Absorption Magnesium Supplement for Leg Cramps, Sleep & Vascular Health - 30 Capsules - Non-GMO Pills for Women
MD.LIFE Store
|
$6.10 | 30d | $6.10 | View on Amazon |
| 37 |
Earthborn Elements Magnesium Oxide, 200 Capsules, Pure & Undiluted, No Additives
Earthborn Elements Store
|
$6.60 | 114d | $21.99 | View on Amazon |
| 38 |
2 Pack Magnesium Oxide 500mg Gummies for Vegan Sugar-Free Raspberry Flavor, Muscle Recovery, Nerve Health & Relaxation, 120 Gummies (Non-GMO, Gluten & Allergen Free)
BVIVLOO Store
|
$7.49 | 75d | $14.99 | View on Amazon |
| 39 |
Mag-Ox 400 Magnesium Supplement, Pharmaceutical Grade Magnesium Oxide with 482 mg Per Dose, 60 Tablets
Mag-Ox 400 Store
|
$7.89 | 36d | $7.89 | View on Amazon |
| 40 |
Magnesium Oxide 500mg Gummies for Vegan Sugar-Free Raspberry Flavor, Muscle Recovery, Nerve Health & Relaxation, 60 Gummies (Non-GMO, Gluten & Allergen Free)
BVIVLOO Store
|
$9.99 | 38d | $9.99 | View on Amazon |
| 41 |
2 Pack Magnesium Oxide Gummies 400mg, Chewable Magnesium Oxide Supplement for Adults, Nerve & Muscle Support - Sugar-Free, Vegan,120 Count
SmildeHeal Store
|
$11.00 | 60d | $21.99 | View on Amazon |
| 42 |
Magnesium Oxide Gummies 400mg, Chewable Magnesium Gummies for Women & Adults, Nerve & Muscle Support - Sugar-Free, Vegan, 60 Count
SmildeHeal Store
|
$11.99 | 30d | $11.99 | View on Amazon |
| 43 |
Mag-Ox 400 Magnesium Supplement, Pharmaceutical Grade Magnesium Oxide with 482 mg Per Dose, 120 Tablets, Pack of 2
Mag-Ox 400 Store
|
$14.29 | 72d | $28.58 | View on Amazon |
Read the elemental magnesium line, usually phrased as "Magnesium (as magnesium oxide)", rather than the oxide compound amount. Labels reviewed for this update included high-elemental-dose tablets, capsules, and digestive/colon-cleanse products using large oxide servings.
Magnesium oxide is often inexpensive per elemental milligram, but monthly cost still depends on serving count, format, and whether the product is a plain mineral or a digestive formula. Very high-dose products may not be intended for routine magnesium repletion.
Do not treat a large oxide compound amount as the elemental magnesium amount. Also separate plain magnesium oxide products from colon-cleanse formulas, where the buyer may be paying for a different use case even though the active mineral is oxide.
Magnesium oxide has strong evidence context as an extensively used magnesium form, though it is generally less bioavailable than many chelated forms. TrueServing compares labeled elemental magnesium cost at 400 mg/day.
TrueServing participates in the Amazon Associates program. We may earn a commission when you purchase through our links at no extra cost to you. Prices are updated regularly but may vary.