Magnesium malate is 12.6–15.5% magnesium by weight and glycinate 11.8–14.1%, so 200 mg of magnesium takes 1,290–1,580 mg of malate or 1,420–1,690 mg of glycinate. Malate's range covers the anhydrous salt and the dihydrate; "dimagnesium malate" is a different compound, and this site does not apply the malate figure to it. Label counts come from the NIH Dietary Supplement Label Database (DSLD) snapshot of 2026-08-10; prices come from Amazon offers observed 2026-10-26 to 2026-11-02 and are compared only inside one salt.
Which to pick for what
At 400 mg of magnesium, both salts need 4–5 size 00 capsules of salt alone: 2,570–3,170 mg of malate or 2,840–3,380 mg of glycinate, by the formulas MgC₄H₄O₅ and Mg(C₂H₄NO₂)₂ at 0.8 g/mL.
- Fewest capsules. For 200 mg of magnesium, either salt needs 2–3 size 00 or 2 size 000 capsules. For 400 mg, either needs 4–5 size 00; in size 000, malate needs 3 and glycinate 3–4. Counts assume salt alone at 0.8 g/mL: 730 mg per size 00, 1,100 mg per size 000.
- Lowest cost inside each salt. 30 days at 400 mg a day from the cheapest ranked malate offer: $5.52. From the cheapest ranked glycinate offer: $7.99. At the median ranked offer, malate: $12.62; glycinate: $22.67. The cheapest malate offer and the cheapest single-salt malate label are not always the same product; the form-by-form winners show both.
- What studies measured. One study in the site's PubMed-checked registry includes both salts:
- PMID 30761462 (2020): absorption of oxide, citrate, glycinate and malate was profiled across several doses, so a comparison at one dose need not hold at another.
- PMID 29679349 (2019): rats received one dose of sulfate, oxide, acetyl taurate, citrate or malate; serum and tissue magnesium, brain included, were followed for hours. Rats, one dose.
- PMID 29425476 (2018): 91 adults at two clinics, 53 of them on a timed-release tablet of dimagnesium malate with vitamins B6 and B12 and folate, the rest on placebo; serum magnesium at 4 and 8 hours and red-cell magnesium to 90 days in 24 of them. Dimagnesium malate is not the malate in this table, and the added vitamins keep the salt's share from being isolated.
- For glycinate: PMID 14596323 (2003; 46 adults, 300 mg a day, amino-acid chelate against citrate and oxide) and PMID 39770988 (2024; 40 adults, plasma magnesium over 6 hours after single doses).
Side by side
For 400 mg of magnesium, glycinate takes 2,840–3,380 mg of compound and malate 2,570–3,170 mg; label counts are from the DSLD snapshot of 2026-08-10 and prices were observed 2026-10-26 to 2026-11-02.
| Measure | Magnesium glycinate | Magnesium malate |
|---|---|---|
| Magnesium by weight | 11.8–14.1% | 12.6–15.5% |
| Compound for 400 mg of magnesium | 2,840–3,380 mg | 2,570–3,170 mg |
| Size 00 capsules for 400 mg (salt alone) | 4–5 | 4–5 |
| Most magnesium one size 000 capsule can hold | 130–155 mg | 139–171 mg |
| Labels in NIH DSLD naming the salt | 126 | 73 |
| Median magnesium per serving on those labels | 238 mg | 321 mg |
| Ranked US price offers | 17 | 4 |
| Lowest price per 100 mg of magnesium, within the salt | $0.0666 | $0.0460 |
Compound masses are rounded to the nearest 10 mg.
What to check on the label
In the DSLD snapshot of 2026-08-10, 20 of 73 malate labels and 73 of 126 glycinate labels name that salt as the only magnesium source.
- Dimagnesium malate. It carries more magnesium per gram than magnesium malate, so the 12.6–15.5% figure does not apply; the site lists it on its own salt page.
- Malic acid. Listed as its own ingredient, it is the free acid and adds no magnesium.
- Magnesium or compound? Supplement Facts should state the magnesium itself. As compound weight, "Magnesium Malate 1,000 mg" holds 126–155 mg of magnesium and "Magnesium Glycinate 400 mg" holds 47–56 mg.
- Per-capsule ceiling. One size 000 capsule holds at most 139–171 mg of magnesium as malate alone and 130–155 mg as glycinate at 0.8 g/mL. The label audit lists labels above their capsule.
- "Buffered" glycinate. The word means an alkaline magnesium salt, usually oxide, is mixed in.
Where to go next
The malate ranking and the glycinate ranking order 4 and 17 ranked offers by price per 100 mg of magnesium, prices observed 2026-10-26 to 2026-11-02.