Same elemental magnesium · two salts · snapshot 2026-08-10
Magnesium carbonate vs malate: 694–807 vs 1,287–1,584 mg of compound for 200 mg of magnesium
Magnesium carbonate is 24.8–28.8% elemental magnesium and magnesium malate is 12.6–15.5%, so 200 mg of magnesium needs 694–807 mg of carbonate against 1,287–1,584 mg of malate: 1–2 vs 2–3 size 00 capsules at powder density 0.8 g/mL, the top of the usual 0.6–0.8 range. No capsule label names carbonate alone, against 0 of 9 for malate. Prices within each salt: no ranked carbonate price; malate from $0.0460 per 100 mg (median $0.1052, 4 ranked offers); observed 2026-10-26 to 2026-11-02.
computed from chemical formulas
Chart data
| Displayed chart text |
|---|
| 100 mg magnesium |
| carbonate 347–404 · malate 644–792 |
| 200 mg magnesium |
| carbonate 694–807 · malate 1,287–1,584 |
| 400 mg magnesium |
| carbonate 1,387–1,614 · malate 2,574–3,167 |
Data release 2026-08-10-f441aa9f · registry snapshot 2026-08-10 · latest price observation 2026-11-02 · chemistry 2026-10-17
How much carbonate or malate carries the same elemental magnesium?
At the same elemental amount, carbonate (24.8–28.8% magnesium) always needs less compound than malate (12.6–15.5%): for 400 mg of magnesium, 1,387–1,614 mg against 2,574–3,167 mg. That is the mass of powder per dose; how much of it is absorbed is what the studies below measured.
computed| Elemental magnesium | carbonate compound | carbonate size 00 | malate compound | malate size 00 |
|---|---|---|---|---|
| 100 mg | 347–404 mg | 1 | 644–792 mg | 1–2 |
| 200 mg | 694–807 mg | 1–2 | 1,287–1,584 mg | 2–3 |
| 400 mg | 1,387–1,614 mg | 2–3 | 2,574–3,167 mg | 4–5 |
carbonate: anhydrous or hydrated; labels rarely state which; malate: anhydrous 15.54% or dihydrate 12.63% (192.41 g/mol); 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
No capsule label names carbonate alone, against 0 of 9 for malate. 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 |
|---|---|---|---|---|
| carbonate | 0 | 0 | 0 | 0 |
| malate | 9 | 7 | 2 | 0 |
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: no ranked carbonate price; malate from $0.0460 per 100 mg (median $0.1052, 4 ranked offers). 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 |
|---|---|---|---|---|
| carbonate | 0 | none | none | 2026-11-02 |
| malate | 4 | $0.0460 | $0.1052 | 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 carbonate and malate side by side?
No study in the PubMed-checked registry measured carbonate and malate side by side as of 2026-08-10; 2 involve carbonate and 3 involve malate separately.
measured| Year | Study | Salts measured | PubMed |
|---|---|---|---|
| 2022 | Effects of short-term magnesium supplementation on ionized, total magnesium and other relevant electrolytes levels. | oxide, citrate, carbonate | 35041150 |
| 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 |
| 2020 | Dose-Dependent Absorption Profile of Different Magnesium Compounds | oxide, citrate, glycinate, malate | 30761462 |
| 2019 | Timeline (Bioavailability) of Magnesium Compounds in Hours: Which Magnesium Compound Works Best? | sulfate, oxide, taurate, citrate, malate | 29679349 |
| 2018 | Scottsdale Magnesium Study: Absorption, Cellular Uptake, and Clinical Effectiveness of a Timed-Release Magnesium Supplement in a Standard Adult Clinical Population. | malate | 29425476 |
Source · PubMed-checked study registry · registry checked 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
How many labels name both carbonate and malate?
4 of 23 labels naming carbonate also name malate as of 2026-08-10; a named blend does not establish how much magnesium each salt contributes.
measured| Label | Declared elemental per serving | NIH DSLD |
|---|---|---|
| Trace Minerals Research Stress-X Magnesium Powder Lemon Lime | 350 mg | 61989 |
| Trace Minerals Research Stress-X Magnesium Powder Lemon Lime | 350 mg | 62023 |
| Trace Minerals Research Stress-X Magnesium Powder Raspberry Lemon | 350 mg | 62021 |
| Trace Minerals Research Stress-X Magnesium Powder Raspberry Lemon | 350 mg | 62026 |
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 | carbonate compound | carbonate size 00 | malate compound | malate size 00 |
|---|---|---|---|---|
| 25 mg | 87–101 mg | 1 | 161–198 mg | 1 |
| 50 mg | 173–202 mg | 1 | 322–396 mg | 1 |
| 75 mg | 260–303 mg | 1 | 483–594 mg | 1 |
| 100 mg | 347–404 mg | 1 | 644–792 mg | 1–2 |
| 125 mg | 434–504 mg | 1 | 804–990 mg | 2 |
| 150 mg | 520–605 mg | 1 | 965–1,188 mg | 2 |
| 175 mg | 607–706 mg | 1 | 1,126–1,386 mg | 2 |
| 200 mg | 694–807 mg | 1–2 | 1,287–1,584 mg | 2–3 |
32 additional rows
| Elemental magnesium | carbonate compound | carbonate size 00 | malate compound | malate size 00 |
|---|---|---|---|---|
| 225 mg | 780–908 mg | 2 | 1,448–1,781 mg | 2–3 |
| 250 mg | 867–1,009 mg | 2 | 1,609–1,979 mg | 3 |
| 275 mg | 954–1,110 mg | 2 | 1,770–2,177 mg | 3 |
| 300 mg | 1,041–1,211 mg | 2 | 1,931–2,375 mg | 3–4 |
| 325 mg | 1,127–1,312 mg | 2 | 2,091–2,573 mg | 3–4 |
| 350 mg | 1,214–1,412 mg | 2 | 2,252–2,771 mg | 4 |
| 375 mg | 1,301–1,513 mg | 2–3 | 2,413–2,969 mg | 4–5 |
| 400 mg | 1,387–1,614 mg | 2–3 | 2,574–3,167 mg | 4–5 |
| 425 mg | 1,474–1,715 mg | 3 | 2,735–3,365 mg | 4–5 |
| 450 mg | 1,561–1,816 mg | 3 | 2,896–3,563 mg | 4–5 |
| 475 mg | 1,648–1,917 mg | 3 | 3,057–3,761 mg | 5–6 |
| 500 mg | 1,734–2,018 mg | 3 | 3,218–3,959 mg | 5–6 |
| 525 mg | 1,821–2,119 mg | 3 | 3,378–4,157 mg | 5–6 |
| 550 mg | 1,908–2,220 mg | 3–4 | 3,539–4,355 mg | 5–6 |
| 575 mg | 1,994–2,320 mg | 3–4 | 3,700–4,553 mg | 6–7 |
| 600 mg | 2,081–2,421 mg | 3–4 | 3,861–4,751 mg | 6–7 |
| 625 mg | 2,168–2,522 mg | 3–4 | 4,022–4,949 mg | 6–7 |
| 650 mg | 2,255–2,623 mg | 4 | 4,183–5,146 mg | 6–8 |
| 675 mg | 2,341–2,724 mg | 4 | 4,344–5,344 mg | 6–8 |
| 700 mg | 2,428–2,825 mg | 4 | 4,505–5,542 mg | 7–8 |
| 725 mg | 2,515–2,926 mg | 4–5 | 4,665–5,740 mg | 7–8 |
| 750 mg | 2,601–3,027 mg | 4–5 | 4,826–5,938 mg | 7–9 |
| 775 mg | 2,688–3,128 mg | 4–5 | 4,987–6,136 mg | 7–9 |
| 800 mg | 2,775–3,228 mg | 4–5 | 5,148–6,334 mg | 8–9 |
| 825 mg | 2,862–3,329 mg | 4–5 | 5,309–6,532 mg | 8–9 |
| 850 mg | 2,948–3,430 mg | 5 | 5,470–6,730 mg | 8–10 |
| 875 mg | 3,035–3,531 mg | 5 | 5,631–6,928 mg | 8–10 |
| 900 mg | 3,122–3,632 mg | 5 | 5,792–7,126 mg | 8–10 |
| 925 mg | 3,208–3,733 mg | 5–6 | 5,952–7,324 mg | 9–11 |
| 950 mg | 3,295–3,834 mg | 5–6 | 6,113–7,522 mg | 9–11 |
| 975 mg | 3,382–3,935 mg | 5–6 | 6,274–7,720 mg | 9–11 |
| 1,000 mg | 3,469–4,036 mg | 5–6 | 6,435–7,918 mg | 9–11 |
Source · Chemical formulas and NIH DSLD labels · snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method