Corrected Calcium Calculator
Calculate albumin-corrected calcium from measured serum calcium and albumin levels. Detect true hypocalcemia or hypercalcemia in hypoalbuminemic patients.
Corrected Magnesium Calculator
Calculate an albumin-adjusted magnesium estimate and review broad magnesium context with a cautious educational worksheet.
⚠️ Medical Disclaimer: This page is an educational worksheet only. Albumin-adjusted magnesium is an estimate, not a universally standardized replacement for direct clinical interpretation.
g/dL
kg
mg/dL
Measured Mg⧉
1.80 mg/dL
As entered (mg/dL)
Albumin-Adjusted Magnesium Estimate⧉
1.80 mg/dL (0.74 mmol/L)
Albumin adjustment: +0.00 mg/dL
Classification⧉
Normal
Within normal range (1.7–2.2 mg/dL).
Albumin Status⧉
Albumin Near Reference
Measured and adjusted values should be similar when albumin is near the reference range.
Rough Magnesium Deficit Worksheet⧉
No estimate shown
The page does not estimate a deficit when the adjusted value is not in the low range.
Renal Function Note⧉
Creatinine is not obviously elevated, but replacement decisions still depend on the full clinical picture.
Magnesium Reference Ranges
| Level | mg/dL | mmol/L | Clinical Significance |
|---|---|---|---|
| Severe Hypomagnesemia | < 1.0 | < 0.41 | Markedly low range; prompt clinical review is usually appropriate |
| Mild Hypomagnesemia | 1.0–1.5 | 0.41–0.62 | Low range; interpret with symptoms, ECG findings, and other electrolytes |
| Borderline Low | 1.5–1.7 | 0.62–0.70 | Borderline range that may still matter in the right clinical context |
| Normal | 1.7–2.2 | 0.70–0.91 | Target range |
| Mildly Elevated | 2.2–2.6 | 0.91–1.07 | Usually iatrogenic; monitor |
| Hypermagnesemia | > 2.6 | > 1.07 | Higher levels can cause hypotension, reduced reflexes, and respiratory compromise |
Dietary Magnesium Sources
| Food | Mg (mg) | % DV (420 mg) | Bar |
|---|---|---|---|
| Pumpkin seeds (1 oz) | 156 | 37% | |
| Spinach, cooked (1 cup) | 157 | 37% | |
| Dark chocolate 70%+ (1 oz) | 64 | 15% | |
| Black beans (1 cup) | 120 | 29% | |
| Almonds (1 oz) | 80 | 19% | |
| Avocado (1 medium) | 58 | 14% | |
| Salmon (3 oz) | 26 | 6% | |
| Banana (1 medium) | 32 | 8% |
Planning notes, formulas, and examples
About the Corrected Magnesium Calculator
The Corrected Magnesium Calculator applies an albumin-adjustment estimate to total serum magnesium so the measured value can be reviewed in the context of low albumin. Because serum magnesium reflects only a small fraction of total body magnesium, and because albumin-adjusted magnesium is not as standardized as albumin-adjusted calcium, this page should be read as a cautious worksheet rather than a definitive diagnostic model.
The output combines the measured magnesium, an albumin-adjusted estimate, broad reference bands, and a rough body-store estimate. That makes it useful for educational review and quick context, but it does not replace direct clinical interpretation, serial lab review, ECG findings, or renal-function assessment.
When This Page Helps
Low albumin can complicate the interpretation of total magnesium. This page keeps the adjustment transparent so the measured value, the albumin-adjusted estimate, and the broad severity bands can be reviewed side by side instead of treated as a single black-box number.
How to Use the Inputs
- Enter the measured serum magnesium level from your lab results.
- Select the unit: mg/dL or mmol/L.
- Enter the serum albumin level (g/dL).
- Enter body weight in kg (used for deficit estimation).
- Enter serum creatinine to assess renal function impact.
- Review the corrected magnesium, classification, and broad interpretation context.
Formula used
Albumin-adjusted Mg estimate (mg/dL) = Measured Mg + 0.005 × (40 − Albumin in g/L)
Where Albumin in g/L = Albumin in g/dL × 10
Unit Conversion: 1 mmol/L Mg = 2.43 mg/dL
Reference Range: 1.7–2.2 mg/dL (0.70–0.91 mmol/L)
Rough body-store estimate (mEq) ≈ (1.9 − Adjusted Mg) × Weight(kg) × 0.3
These adjustment and deficit formulas are approximations for educational review, not validated replacement protocols.Example Calculation
Result: Corrected Mg = 1.88 mg/dL — Normal
Measured Mg is 1.8 mg/dL, albumin is 2.5 g/dL (25 g/L). Correction: 1.8 + 0.005 × (40 − 25) = 1.8 + 0.075 = 1.875. With significant hypoalbuminemia, the corrected value is slightly higher but still within the normal range.
Tips & Best Practices
- Albumin-adjusted magnesium is less standardized than albumin-adjusted calcium, so borderline results should be read cautiously.
- Refractory hypokalemia or hypocalcemia can coexist with magnesium deficiency, but this page is not a treatment protocol.
- Proton pump inhibitors, GI losses, renal losses, and alcohol use are common reasons to review magnesium more closely.
- If the result is markedly low or high, the next step is clinical evaluation rather than relying on the worksheet alone.
- When the clinical picture is important, trend the magnesium alongside potassium, calcium, phosphate, renal function, and ECG findings.
- Dietary magnesium tables are supportive context only; they do not substitute for medical evaluation or replacement planning.
Magnesium Physiology
Magnesium is the fourth most abundant cation in the body and the second most abundant intracellular cation after potassium. It is a cofactor for over 300 enzymatic reactions including ATP synthesis, DNA replication, protein synthesis, and neuromuscular function. Only 1% of total body magnesium is in the serum, making blood levels a poor indicator of total body stores.
Clinical Significance of Magnesium Disorders
Hypomagnesemia causes neuromuscular irritability (tremors, tetany, seizures), cardiac arrhythmias (prolonged QT, torsades de pointes, atrial and ventricular arrhythmias), and electrolyte disturbances (refractory hypokalemia and hypocalcemia). Chronic deficiency is associated with type 2 diabetes, hypertension, cardiovascular disease, osteoporosis, and migraine headaches.
Interpreting Magnesium in Context
Always interpret magnesium alongside potassium, calcium, and phosphate levels. In diabetic ketoacidosis, total body magnesium can be depleted even if serum levels appear normal because hemoconcentration may mask the deficit. As treatment and fluid are given, magnesium may fall further, which is why the broader clinical picture matters more than the worksheet alone.
Sources & Methodology
Last updated:
Methodology
This page calculates an albumin-adjusted estimate from measured total magnesium and albumin, then places the value beside broad magnesium reference bands and a rough body-store estimate. It is included as a cautious interpretation worksheet because serum magnesium reflects only a small fraction of total body magnesium and albumin-adjusted magnesium is not a uniformly standardized clinical measure.
The output is not a validated replacement protocol, and it should not be used to prescribe IV or oral magnesium by itself. Symptoms, ECG changes, renal function, calcium or potassium abnormalities, and repeat labs matter more than the worksheet alone.
Sources
- Magnesium: The Forgotten Electrolyte-A Review on Hypomagnesemia (PubMed / Medicina) — Broad clinical review of magnesium physiology, causes of hypomagnesemia, and interpretation limits of serum magnesium.
- The Laboratory and Clinical Perspectives of Magnesium Imbalance (PubMed / Diagnostics) — Recent laboratory-focused review highlighting the limitations of simple serum magnesium assessment and the broader clinical context required.
Frequently Asked Questions
A portion of serum magnesium is protein-bound, so low albumin can complicate interpretation of the measured total magnesium. The adjustment shown here is meant as a cautious estimate rather than a universally accepted clinical standard.
Common causes include chronic alcohol use, poor intake, GI losses such as diarrhea or vomiting, renal wasting from diuretics, proton pump inhibitor use, diabetic ketoacidosis, pancreatitis, and some medications such as cisplatin, amphotericin B, and calcineurin inhibitors.
No. The page is not a dosing or infusion protocol. Replacement decisions depend on symptoms, ECG findings, renal function, route of administration, concomitant electrolyte abnormalities, and the treatment setting.
Different magnesium salts have different tolerability and bioavailability, but this page does not rank products or prescribe a replacement regimen. That choice should be individualized to the clinical situation.
Yes. Hypermagnesemia (> 2.6 mg/dL) causes hypotension, bradycardia, decreased deep tendon reflexes, and at very high levels (> 7 mg/dL), respiratory depression and cardiac arrest. It typically occurs with renal failure combined with magnesium supplementation.
Ionized magnesium is conceptually closer to the biologically active fraction, but testing is less available and not uniformly standardized. That is one reason this page should be treated as an estimate worksheet rather than as a definitive magnesium-status standard.
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