Label arithmetic · NIH DSLD 329882
BulkSupplements.com Magnesium Citrate Capsules 400 mg: 80 mg of magnesium per capsule, 5 capsules a day
80 mg of magnesium per capsule; the label's 5 capsules a day give 400 mg. No US price matched (Nov 2). Inside: salt weight, capsule size.
BulkSupplements.com Magnesium Citrate Capsules 400 mg declares 400 mg of elemental magnesium per serving as citrate, which needs 495–708 mg of magnesium citrate in each capsule, against 545 mg in a size 0 capsule at powder density 0.8 g/mL, the top of the usual 0.6–0.8 range: it fits a size 0 capsule, the smallest of the three sizes compared here. No US retail price matched as of 2026-11-02; 17 of the 135 citrate labels in this registry have a matched price. NIH DSLD 329882, label dated 2025-04-24.
computed from the filed label
Chart data
| Displayed chart text |
|---|
| 545 mg |
| 730 mg |
| 1,100 mg |
| 495–708 mg of citrate per capsule |
Data release 2026-08-10-f441aa9f · registry snapshot 2026-08-10 · latest price observation 2026-10-19 · chemistry 2026-10-17
Mass: 495–708 mg per capsule · Price: none matched · % DV: 95% vs 95%
Elemental: The magnesium itself; the rest of the compound weight is the partner molecule.
Compound: The whole salt, such as magnesium glycinate, that must physically fit in the capsule.
Size 000: The largest standard capsule, about 1,100 mg of powder at 0.8 g/mL, the top of the usual 0.6–0.8 range; size 00 holds about 730 mg and size 0 about 545 mg.
Recompute with your price
Enter the price you paid; the declared amount and servings of this label are prefilled, so the result is the cost per 100 mg of elemental magnesium for your bottle.
Same-salt comparison appears here.
Will 400 mg of citrate actually fit in one capsule, or do I need more than one?
Estimated salt mass versus assumed capsule capacity: BulkSupplements.com Magnesium Citrate Capsules 400 mg implies 495–708 mg of magnesium citrate in each capsule to deliver 400 mg of elemental magnesium, against 1,100 mg in the largest standard capsule (size 000) at powder density 0.8 g/mL, the top of the usual 0.6–0.8 range. Verdict: fits size 0, read at the most favourable hydration and the most units per serving.
computed with assumption| Measure | Value |
|---|---|
| Elemental magnesium per serving | 400 mg |
| Units per serving | 5 |
| Magnesium citrate per serving | 2,475–3,540 mg |
| Magnesium citrate per capsule | 495–708 mg |
| Capsule capacity 0 · 00 · 000 | 545 · 730 · 1,100 mg |
| Verdict | Fits size 0 |
The filed salt can have more than one hydration state (trimagnesium dicitrate 16.2%; dibasic and hydrated forms as low as 11.3%), so the compound mass is a range.
Source · NIH DSLD 329882 · label 2025-04-24; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
How much elemental magnesium is actually in this label's filed magnesium lines?
BulkSupplements.com Magnesium Citrate Capsules 400 mg files 1 magnesium line in NIH DSLD 329882; the selected primary line declares 400 mg of elemental magnesium per serving, against 0 other rows excluded from the primary amount. A salt named under another nutrient does not turn that nutrient's quantity into elemental magnesium.
measured| Filed amount | Salt or note as filed | Role |
|---|---|---|
| 400 mg | Salt not named in this row; magnesium citrate is taken from the label text | Primary serving |
Source · NIH DSLD 329882 · label 2025-04-24; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Does this label's citrate claim hold up, or could the magnesium come from another source?
The label names one magnesium form, citrate, resolved from the full NIH DSLD record text; at that salt the declaration is within the assumed size 000 capacity at powder density 0.8 g/mL, compared with oxide, the salt richest in magnesium at 60.3%.
computed with assumption| Form named on the label | Elemental fraction | Source |
|---|---|---|
| Magnesium citrate | 11.3–16.2% | full NIH DSLD record text |
Source · NIH DSLD 329882 · label 2025-04-24; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Is this a good price for the elemental magnesium I'm actually getting?
No US retail price is matched to this label as of 2026-11-02; 17 of 135 citrate labels have one, against a median of $0.1159 per 100 mg among 12 ranked citrate offers.
computed
Chart data
| Displayed chart text |
|---|
| n=12 |
| P25 $0.0843 |
| P75 $0.1469 |
| median $0.1159 |
| Rank | Label | Per 100 mg | Observed |
|---|---|---|---|
| 1 | Best Naturals Magnesium Citrate 200 mg | $0.0344 | 2026-11-02 |
| 2 | Solgar Magnesium Citrate | $0.0607 | 2026-11-02 |
| 3 | LES Labs Magnesium Citrate | $0.0777 | 2026-11-02 |
| 4 | Bluebonnet Magnesium Citrate | $0.0865 | 2026-11-02 |
| 5 | Solaray Magnesium Citrate 400 mg | $0.0868 | 2026-11-02 |
| Median | 12 ranked citrate offers | $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
How many days will this bottle last at the label's own serving, and what does a day cost?
At the label's own serving, BulkSupplements.com Magnesium Citrate Capsules 400 mg lasts 60 days: 60 servings against 1 serving a day in the filed directions.
computed| Measure | Value |
|---|---|
| Net contents as filed | 300 Capsule(s) |
| Serving size as filed | 5 Capsule(s) |
| Servings per container | 60 |
| Servings per day in the directions | 1 |
| Days per bottle | 60 days |
| $ per 30 days at one label serving a day | No ranked price as of 2026-11-02 |
| $ per 30 days at 420 mg Daily Value | No ranked price as of 2026-11-02 |
Source · NIH DSLD 329882 · label 2025-04-24; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
What does "95% Daily Value" mean here, and does it recompute?
The label declares 95% Daily Value; 400 mg against the 420 mg reference in 21 CFR 101.9 recomputes to 95%, the same within one point.
computed| Group as filed | Declared | Reference | Recomputed |
|---|---|---|---|
| Adults and children 4 or more years of age | 95% | 420 mg | 95% |
Source · NIH DSLD 329882; 21 CFR 101.9 · label 2025-04-24 · release 2026-08-10-f441aa9f · CSV · method
Why does this label contain these other ingredients, what shell is it, and who is it filed for?
BulkSupplements.com Magnesium Citrate Capsules 400 mg files 1 other ingredient and a gelatin shell, and no magnesium stearate, against 43 of 135 citrate labels that list magnesium stearate.
measured| Entry | Filed ingredient or declaration |
|---|---|
| 1 | Bovine Gelatin |
| Shell | gelatin |
| Target group | Adult (18 - 50 Years) |
| Target group | Gluten Free |
| Target group | Dairy Free |
| Target group | Sugar Free |
Source · NIH DSLD 329882 · label 2025-04-24; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
What has research measured about citrate, and about side effects?
10 studies in the PubMed-checked registry measured outcomes involving citrate; 1 mention gastrointestinal or adverse outcomes. They measured the salt, not this label.
measured| Year | Study | PubMed |
|---|---|---|
| 2025 | Comparing the Bioavailability of Two Seawater-Derived Magnesium Preparations. | 40955524 |
| 2024 | Comparative Clinical Study on Magnesium Absorption and Side Effects After Oral Intake of Microencapsulated Magnesium (MAGSHAPE™ Microcapsules) Versus Other Magnesium Sources. | 39770988 |
| 2022 | Effects of short-term magnesium supplementation on ionized, total magnesium and other relevant electrolytes levels. | 35041150 |
Source · PubMed-checked study registry · registry checked 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Has this brand had FDA recalls or adverse event reports?
BulkSupplements.com has 2 FDA recall records matched by brand name in the enforcement data queried 2026-10-19. BulkSupplements.com has FDA CAERS adverse event reports on record at brand level, as do 143 of 273 brands in this registry; openFDA states that “there is no certainty that the reported event (adverse event) was actually due to the product” and that reports “cannot be used to estimate the incidence of these events.”
measured| Recall | Date | Reason | Status |
|---|---|---|---|
| F-1827-2018 | 2018-08-22 | FDA inspection found two lots of supplements that did not declare shellfish as an ingredient on the product label; shellfish is properly declared on website. | Terminated |
| H-0619-2025 | 2025-09-24 | Finished product possibly contaminated with pathogenic Staphylococcus aureus. | Terminated |
Source · openFDA enforcement and CAERS · queried 2026-10-19 · release 2026-08-10-f441aa9f · CSV · method
Is this the same formula as another brand's, and how do their prices differ?
No other brand files the same formulation (ingredients, shell, units and rounded amount) as of 2026-11-02.
computed| Label | Brand | Price per 100 mg |
|---|---|---|
| No cross-brand match as of 2026-11-02 |
Source · NIH DSLD 329882 · label 2025-04-24; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Which labels are closest to this one, with the same salt and dose?
5 labels use the same resolved citrate within ±10% of this label's 80 mg per unit, compared side by side on price and capsule verdict.
computed| Label | Elemental per unit | Price | Verdict |
|---|---|---|---|
| BulkSupplements.com Magnesium Citrate 3500 mg Capsules | 80 mg | $20.96 · 2026-10-12 | Fits size 0 |
| KAL Magnesium Citrate Orange Vanilla | 83 mg | No price | Capsule sizes do not apply |
| Lifeable Magnesium Citrate Fruit Flavor | 83 mg | $19.99 · 2026-11-02 | Capsule sizes do not apply |
| Bio-Tech Pharmacal Magnesium Citrate (DSLD 217402) | 75 mg | No price | Fits size 0 |
| Bio-Tech Pharmacal Magnesium Citrate (DSLD 217403) | 75 mg | No price | Fits size 0 |
Source · NIH DSLD 329882 · label 2025-04-24; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Where does this record come from, what is missing, and how do I cite or correct it?
Every value on this page traces to NIH DSLD 329882 (label 2025-04-24, snapshot 2026-08-10) and the chemistry model of 2026-09-13. 1 gap remain: No US retail price matched as of 2026-11-02 (barcode X002KVPVOX). The CSV carries the values shown here.
measured| Field | As filed |
|---|---|
| NIH DSLD label | NIH DSLD 329882 |
| Scanned label (PDF) | Label 329882 scan |
| Label date | 2025-04-24 |
| Date entered into DSLD | 2025-04-24 |
| Barcode (UPC) as filed | X002KVPVOX |
| Distributed exclusively by | BulkSupplements.com, Henderson, NV, USA |
| Claim category as filed | Nutrient |
| Claim category as filed | All Other |
11 additional rows
| Field | As filed |
|---|---|
| Claim category as filed | Structure/Function |
| Formula re: Contains | 400 mg of magnesium |
| Suggested/Recommended/Usage/Directions | Suggested use: As a dietary supplement, take 5 capsules daily, or as directed by a physician. |
| Formulation re: Does NOT Contain | Free of: sugar, soy, yeast, dairy, gluten, additives |
| Storage | Store in a dry, cool place |
| General Statements: All Other Content | Scan me New |
| FDA Disclaimer Statement | Warning: This product is not intended to diagnose, treat, cure, or prevent any disease. |
| Precautions re: All Other | Always consult a physician before taking any dietary supplement. |
| Precautions re: Children | Keep out of reach of children. |
| Physical state | Capsule |
| Registry snapshot | 2026-08-10 |
Source · NIH DSLD 329882 · label 2025-04-24; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
6 brand pages linked below contain magnesium labels from the NIH DSLD registry snapshot dated 2026-08-10.