Same elemental magnesium · two salts · snapshot 2026-08-10
Magnesium glycinate vs hydroxide: 1,418–1,691 vs 480 mg of compound for 200 mg of magnesium
Magnesium glycinate is 11.8–14.1% elemental magnesium and magnesium hydroxide is 41.7%, so 200 mg of magnesium needs 1,418–1,691 mg of glycinate against 480 mg of hydroxide: 2–3 vs 1 size 00 capsules at powder density 0.8 g/mL, the top of the usual 0.6–0.8 range. 3 of 25 capsule labels naming glycinate alone are above the assumed size 000 capacity at powder density 0.8 g/mL, against none for hydroxide (no capsule label names it alone). Prices within each salt: glycinate from $0.0666 per 100 mg (median $0.1889, 17 ranked offers); no ranked hydroxide price; observed 2026-10-26 to 2026-11-02.
computed from chemical formulas
Chart data
| Displayed chart text |
|---|
| 100 mg magnesium |
| hydroxide 240 · glycinate 709–845 |
| 200 mg magnesium |
| hydroxide 480 · glycinate 1,418–1,691 |
| 400 mg magnesium |
| hydroxide 960 · glycinate 2,837–3,381 |
Data release 2026-08-10-f441aa9f · registry snapshot 2026-08-10 · latest price observation 2026-11-02 · chemistry 2026-10-17
How much glycinate or hydroxide carries the same elemental magnesium?
At the same elemental amount, hydroxide (41.7% magnesium) always needs less compound than glycinate (11.8–14.1%): for 400 mg of magnesium, 960 mg against 2,837–3,381 mg. That is the mass of powder per dose; how much of it is absorbed is what the studies below measured.
computed| Elemental magnesium | glycinate compound | glycinate size 00 | hydroxide compound | hydroxide size 00 |
|---|---|---|---|---|
| 100 mg | 709–845 mg | 1–2 | 240 mg | 1 |
| 200 mg | 1,418–1,691 mg | 2–3 | 480 mg | 1 |
| 400 mg | 2,837–3,381 mg | 4–5 | 960 mg | 2 |
glycinate: bisglycinate; chelate hydration varies by supplier; hydration ambiguity stays a range.
Source · Chemical formulas and NIH DSLD labels · snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Estimated salt mass versus assumed capsule capacity
3 of 25 capsule labels naming glycinate alone are above the assumed size 000 capacity at powder density 0.8 g/mL, against none for hydroxide (no capsule label names it alone). Verdicts use the most favourable hydration and the most units per serving at powder density 0.8 g/mL, the top of the usual 0.6–0.8 range; the audited registry as a whole has 8 of 137 capsule labels above size 000.
computed with assumption| Salt | Audited capsule labels | Fits 0 or 00 | Needs 000 | Exceeds 000 |
|---|---|---|---|---|
| glycinate | 25 | 14 | 8 | 3 |
| hydroxide | 0 | 0 | 0 | 0 |
Source · NIH DSLD labels; mass balance · recognized salt only; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Which glycinate and hydroxide labels are above the assumed size 000 capacity at powder density 0.8 g/mL?
3 of 25 glycinate capsule labels declare more magnesium than the named salt alone can deliver from a size 000 capsule, at the most favourable hydration and units per serving; each row opens the label's own arithmetic.
computed with assumption| Label | Salt | Salt per capsule | Verdict |
|---|---|---|---|
| eXplicit Supplements Magnesium Glycinate 425 mg | glycinate | 1,507 mg | exceeds size 000 |
| NutriONN Magnesium Glycinate 1600 mg | glycinate | 1,418 mg | exceeds size 000 |
| Swolverine Magnesium Bisglycinate | glycinate | 1,418 mg | exceeds size 000 |
Source · NIH DSLD labels; mass balance · recognized salt only; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
What does each cost per 100 mg of elemental magnesium, within its own salt?
Compared only with offers of the same salt: glycinate from $0.0666 per 100 mg (median $0.1889, 17 ranked offers); no ranked hydroxide price. Prices observed 2026-10-26 to 2026-11-02; a ranking exists only inside one salt, because the compound mass per 100 mg of magnesium differs between salts.
computed| Salt | Ranked offers | Lowest per 100 mg | Median per 100 mg | Observed |
|---|---|---|---|---|
| glycinate | 17 | $0.0666 | $0.1889 | 2026-11-02 |
| hydroxide | 0 | none | none | 2026-11-02 |
Source · Amazon via licensed data provider; NIH DSLD · unique ASIN × date; prices observed 2026-10-26 to 2026-11-02 · release 2026-08-10-f441aa9f · CSV · method
Has any study measured glycinate and hydroxide side by side?
No study in the PubMed-checked registry measured glycinate and hydroxide side by side as of 2026-08-10; 6 involve glycinate and 1 involve hydroxide separately.
measured| Year | Study | Salts measured | PubMed |
|---|---|---|---|
| 2024 | Comparative Clinical Study on Magnesium Absorption and Side Effects After Oral Intake of Microencapsulated Magnesium (MAGSHAPE™ Microcapsules) Versus Other Magnesium Sources. | citrate, glycinate, oxide | 39770988 |
| 2024 | The bioaccessibility and tolerability of marine-derived sources of magnesium and calcium. | glycinate | 38608850 |
| 2020 | Dose-Dependent Absorption Profile of Different Magnesium Compounds | oxide, citrate, glycinate, malate | 30761462 |
| 2005 | Study of magnesium bioavailability from ten organic and inorganic Mg salts in Mg-depleted rats using a stable isotope approach | oxide, chloride, sulfate, carbonate, citrate, gluconate, lactate, aspartate, glycinate | 16548135 |
| 2003 | Mg citrate found more bioavailable than other Mg preparations in a randomised, double-blind study | citrate, oxide, glycinate | 14596323 |
| 1995 | Bioavailability of magnesium diglycinate vs magnesium oxide in patients with ileal resection | glycinate, oxide | 7815675 |
| 2025 | Comparing the Bioavailability of Two Seawater-Derived Magnesium Preparations. | citrate, hydroxide | 40955524 |
Source · PubMed-checked study registry · registry checked 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
How many labels name both glycinate and hydroxide?
No label names both glycinate and hydroxide as of 2026-08-10, against 126 labels naming glycinate and 10 naming hydroxide.
measured| Label | Declared elemental per serving | NIH DSLD |
|---|---|---|
| No label as of 2026-08-10 |
Source · Chemical formulas and NIH DSLD labels · snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
What does every dose from 25 to 1,000 mg of magnesium need in each salt?
The table converts 40 elemental amounts, 25 to 1,000 mg in 25 mg steps, into compound mass and size 00 capsules for both salts, against 730 mg per size 00 capsule at powder density 0.8 g/mL, the top of the usual 0.6–0.8 range. The first eight rows are shown; the rest open below.
computed| Elemental magnesium | glycinate compound | glycinate size 00 | hydroxide compound | hydroxide size 00 |
|---|---|---|---|---|
| 25 mg | 177–211 mg | 1 | 60 mg | 1 |
| 50 mg | 355–423 mg | 1 | 120 mg | 1 |
| 75 mg | 532–634 mg | 1 | 180 mg | 1 |
| 100 mg | 709–845 mg | 1–2 | 240 mg | 1 |
| 125 mg | 887–1,057 mg | 2 | 300 mg | 1 |
| 150 mg | 1,064–1,268 mg | 2 | 360 mg | 1 |
| 175 mg | 1,241–1,479 mg | 2–3 | 420 mg | 1 |
| 200 mg | 1,418–1,691 mg | 2–3 | 480 mg | 1 |
32 additional rows
| Elemental magnesium | glycinate compound | glycinate size 00 | hydroxide compound | hydroxide size 00 |
|---|---|---|---|---|
| 225 mg | 1,596–1,902 mg | 3 | 540 mg | 1 |
| 250 mg | 1,773–2,113 mg | 3 | 600 mg | 1 |
| 275 mg | 1,950–2,325 mg | 3–4 | 660 mg | 1 |
| 300 mg | 2,128–2,536 mg | 3–4 | 720 mg | 1 |
| 325 mg | 2,305–2,747 mg | 4 | 780 mg | 2 |
| 350 mg | 2,482–2,959 mg | 4–5 | 840 mg | 2 |
| 375 mg | 2,660–3,170 mg | 4–5 | 900 mg | 2 |
| 400 mg | 2,837–3,381 mg | 4–5 | 960 mg | 2 |
| 425 mg | 3,014–3,593 mg | 5 | 1,020 mg | 2 |
| 450 mg | 3,191–3,804 mg | 5–6 | 1,080 mg | 2 |
| 475 mg | 3,369–4,015 mg | 5–6 | 1,140 mg | 2 |
| 500 mg | 3,546–4,227 mg | 5–6 | 1,200 mg | 2 |
| 525 mg | 3,723–4,438 mg | 6–7 | 1,260 mg | 2 |
| 550 mg | 3,901–4,649 mg | 6–7 | 1,320 mg | 2 |
| 575 mg | 4,078–4,861 mg | 6–7 | 1,380 mg | 2 |
| 600 mg | 4,255–5,072 mg | 6–7 | 1,440 mg | 2 |
| 625 mg | 4,433–5,283 mg | 7–8 | 1,500 mg | 3 |
| 650 mg | 4,610–5,495 mg | 7–8 | 1,560 mg | 3 |
| 675 mg | 4,787–5,706 mg | 7–8 | 1,619 mg | 3 |
| 700 mg | 4,965–5,917 mg | 7–9 | 1,679 mg | 3 |
| 725 mg | 5,142–6,128 mg | 8–9 | 1,739 mg | 3 |
| 750 mg | 5,319–6,340 mg | 8–9 | 1,799 mg | 3 |
| 775 mg | 5,496–6,551 mg | 8–9 | 1,859 mg | 3 |
| 800 mg | 5,674–6,762 mg | 8–10 | 1,919 mg | 3 |
| 825 mg | 5,851–6,974 mg | 9–10 | 1,979 mg | 3 |
| 850 mg | 6,028–7,185 mg | 9–10 | 2,039 mg | 3 |
| 875 mg | 6,206–7,396 mg | 9–11 | 2,099 mg | 3 |
| 900 mg | 6,383–7,608 mg | 9–11 | 2,159 mg | 3 |
| 925 mg | 6,560–7,819 mg | 9–11 | 2,219 mg | 4 |
| 950 mg | 6,738–8,030 mg | 10–12 | 2,279 mg | 4 |
| 975 mg | 6,915–8,242 mg | 10–12 | 2,339 mg | 4 |
| 1,000 mg | 7,092–8,453 mg | 10–12 | 2,399 mg | 4 |
Source · Chemical formulas and NIH DSLD labels · snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method