Same elemental magnesium · two salts · snapshot 2026-08-10
Magnesium chloride vs citrate: 783–1,672 vs 1,238–1,770 mg of compound for 200 mg of magnesium
Magnesium chloride is 12.0–25.5% elemental magnesium and magnesium citrate is 11.3–16.2%, so 200 mg of magnesium needs 783–1,672 mg of chloride against 1,238–1,770 mg of citrate: 2–3 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 chloride alone, against 5 of 62 for citrate. Prices within each salt: no ranked chloride price; citrate from $0.0344 per 100 mg (median $0.1159, 12 ranked offers); observed 2026-10-26 to 2026-11-02.
computed from chemical formulas
Chart data
| Displayed chart text |
|---|
| 100 mg magnesium |
| chloride 392–836 · citrate 619–885 |
| 200 mg magnesium |
| chloride 783–1,672 · citrate 1,238–1,770 |
| 400 mg magnesium |
| chloride 1,567–3,344 · citrate 2,475–3,540 |
Data release 2026-08-10-f441aa9f · registry snapshot 2026-08-10 · latest price observation 2026-11-02 · chemistry 2026-10-17
How much chloride or citrate carries the same elemental magnesium?
At the same elemental amount, chloride (12.0–25.5% magnesium) always needs less compound than citrate (11.3–16.2%): for 400 mg of magnesium, 1,567–3,344 mg against 2,475–3,540 mg. That is the mass of powder per dose; how much of it is absorbed is what the studies below measured.
computed| Elemental magnesium | chloride compound | chloride size 00 | citrate compound | citrate size 00 |
|---|---|---|---|---|
| 100 mg | 392–836 mg | 1–2 | 619–885 mg | 1–2 |
| 200 mg | 783–1,672 mg | 2–3 | 1,238–1,770 mg | 2–3 |
| 400 mg | 1,567–3,344 mg | 3–5 | 2,475–3,540 mg | 4–5 |
chloride: anhydrous 25.5%, hexahydrate 12.0%; citrate: trimagnesium dicitrate 16.2%; dibasic and hydrated forms as low as 11.3%; 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 chloride alone, against 5 of 62 for citrate. 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 |
|---|---|---|---|---|
| chloride | 0 | 0 | 0 | 0 |
| citrate | 62 | 25 | 32 | 5 |
Source · NIH DSLD labels; mass balance · recognized salt only; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Which chloride and citrate labels are above the assumed size 000 capacity at powder density 0.8 g/mL?
5 of 62 citrate 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 |
|---|---|---|---|
| Vitamin World Magnesium Citrate 250 mg | citrate | 1,547 mg | exceeds size 000 |
| Biotech Nutritions Magnesium Citrate | citrate | 1,392 mg | exceeds size 000 |
| Nutricost Magnesium Citrate 420 mg | citrate | 1,300 mg | exceeds size 000 |
| Evlution Nutrition Magnesium Citrate 400 mg | citrate | 1,238 mg | exceeds size 000 |
| NuMedica Magnesium Citrate Extra Strength 200 mg | citrate | 1,238 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: no ranked chloride price; citrate from $0.0344 per 100 mg (median $0.1159, 12 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 |
|---|---|---|---|---|
| chloride | 0 | none | none | 2026-11-02 |
| citrate | 12 | $0.0344 | $0.1159 | 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 chloride and citrate side by side?
One study in the PubMed-checked registry measured both salts in the same design; 3 involve chloride and 10 involve citrate in total. They measured outcomes of the salts, not of any label.
measured| Year | Study | Salts measured | PubMed |
|---|---|---|---|
| 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 |
| 2001 | Bioavailability of US commercial magnesium preparations | oxide, chloride, lactate, aspartate | 11794633 |
| 1992 | Blood and urinary magnesium kinetics after oral magnesium supplements. | chloride, gluconate | 1468087 |
| 2025 | Comparing the Bioavailability of Two Seawater-Derived Magnesium Preparations. | citrate, hydroxide | 40955524 |
| 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 |
| 2022 | Effects of short-term magnesium supplementation on ionized, total magnesium and other relevant electrolytes levels. | oxide, citrate, carbonate | 35041150 |
| 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 |
4 additional rows
| Year | Study | Salts measured | PubMed |
|---|---|---|---|
| 2012 | Comparison of magnesium status using X-ray dispersion analysis following magnesium oxide and magnesium citrate treatment of healthy subjects | citrate, oxide | 22433473 |
| 2003 | Mg citrate found more bioavailable than other Mg preparations in a randomised, double-blind study | citrate, oxide, glycinate | 14596323 |
| 1990 | Magnesium bioavailability from magnesium citrate and magnesium oxide | citrate, oxide | 2407766 |
| 1990 | Effect of magnesium citrate and magnesium oxide on the crystallization of calcium salts in urine | citrate, oxide | 2299712 |
Source · PubMed-checked study registry · registry checked 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
How many labels name both chloride and citrate?
No label names both chloride and citrate as of 2026-08-10, against 19 labels naming chloride and 212 naming citrate.
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 | chloride compound | chloride size 00 | citrate compound | citrate size 00 |
|---|---|---|---|---|
| 25 mg | 98–209 mg | 1 | 155–221 mg | 1 |
| 50 mg | 196–418 mg | 1 | 309–442 mg | 1 |
| 75 mg | 294–627 mg | 1 | 464–664 mg | 1 |
| 100 mg | 392–836 mg | 1–2 | 619–885 mg | 1–2 |
| 125 mg | 490–1,045 mg | 1–2 | 774–1,106 mg | 2 |
| 150 mg | 588–1,254 mg | 1–2 | 928–1,327 mg | 2 |
| 175 mg | 685–1,463 mg | 1–3 | 1,083–1,549 mg | 2–3 |
| 200 mg | 783–1,672 mg | 2–3 | 1,238–1,770 mg | 2–3 |
32 additional rows
| Elemental magnesium | chloride compound | chloride size 00 | citrate compound | citrate size 00 |
|---|---|---|---|---|
| 225 mg | 881–1,881 mg | 2–3 | 1,392–1,991 mg | 2–3 |
| 250 mg | 979–2,090 mg | 2–3 | 1,547–2,212 mg | 3–4 |
| 275 mg | 1,077–2,299 mg | 2–4 | 1,702–2,434 mg | 3–4 |
| 300 mg | 1,175–2,508 mg | 2–4 | 1,856–2,655 mg | 3–4 |
| 325 mg | 1,273–2,717 mg | 2–4 | 2,011–2,876 mg | 3–4 |
| 350 mg | 1,371–2,926 mg | 2–5 | 2,166–3,097 mg | 3–5 |
| 375 mg | 1,469–3,135 mg | 3–5 | 2,321–3,319 mg | 4–5 |
| 400 mg | 1,567–3,344 mg | 3–5 | 2,475–3,540 mg | 4–5 |
| 425 mg | 1,665–3,554 mg | 3–5 | 2,630–3,761 mg | 4–6 |
| 450 mg | 1,763–3,763 mg | 3–6 | 2,785–3,982 mg | 4–6 |
| 475 mg | 1,861–3,972 mg | 3–6 | 2,939–4,204 mg | 5–6 |
| 500 mg | 1,958–4,181 mg | 3–6 | 3,094–4,425 mg | 5–7 |
| 525 mg | 2,056–4,390 mg | 3–7 | 3,249–4,646 mg | 5–7 |
| 550 mg | 2,154–4,599 mg | 3–7 | 3,403–4,867 mg | 5–7 |
| 575 mg | 2,252–4,808 mg | 4–7 | 3,558–5,088 mg | 5–7 |
| 600 mg | 2,350–5,017 mg | 4–7 | 3,713–5,310 mg | 6–8 |
| 625 mg | 2,448–5,226 mg | 4–8 | 3,868–5,531 mg | 6–8 |
| 650 mg | 2,546–5,435 mg | 4–8 | 4,022–5,752 mg | 6–8 |
| 675 mg | 2,644–5,644 mg | 4–8 | 4,177–5,973 mg | 6–9 |
| 700 mg | 2,742–5,853 mg | 4–9 | 4,332–6,195 mg | 6–9 |
| 725 mg | 2,840–6,062 mg | 4–9 | 4,486–6,416 mg | 7–9 |
| 750 mg | 2,938–6,271 mg | 5–9 | 4,641–6,637 mg | 7–10 |
| 775 mg | 3,036–6,480 mg | 5–9 | 4,796–6,858 mg | 7–10 |
| 800 mg | 3,134–6,689 mg | 5–10 | 4,950–7,080 mg | 7–10 |
| 825 mg | 3,231–6,898 mg | 5–10 | 5,105–7,301 mg | 7–11 |
| 850 mg | 3,329–7,107 mg | 5–10 | 5,260–7,522 mg | 8–11 |
| 875 mg | 3,427–7,316 mg | 5–11 | 5,415–7,743 mg | 8–11 |
| 900 mg | 3,525–7,525 mg | 5–11 | 5,569–7,965 mg | 8–11 |
| 925 mg | 3,623–7,734 mg | 5–11 | 5,724–8,186 mg | 8–12 |
| 950 mg | 3,721–7,943 mg | 6–11 | 5,879–8,407 mg | 9–12 |
| 975 mg | 3,819–8,152 mg | 6–12 | 6,033–8,628 mg | 9–12 |
| 1,000 mg | 3,917–8,361 mg | 6–12 | 6,188–8,850 mg | 9–13 |
Source · Chemical formulas and NIH DSLD labels · snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method