# Calcium Unit Converter (mg/dL ↔ mmol/L)

Convert total serum calcium between mg/dL and mmol/L. Factor 0.25 (atomic weight 40.078; × 4.0 inverse). Does not albumin-correct. Derived from Payne 1973, Young 1987, StatPearls, Endocrine Society. Not medical advice.

> Canonical page: https://elysiatools.com/en/tools/calcium-unit-converter

- **Category:** Health

- **Keywords:** calcium converter, calcium unit, serum calcium, total calcium, mg dl, mmol l, hypercalcemia, hypocalcemia, electrolyte, endocrinology, si units, lab medicine

## Overview

Convert measured total serum calcium between mg/dL and mmol/L using the fixed factor 0.25, with the inverse conversion using ×4.0. Choose the input and target units, enter a value, and set the desired decimal places. This tool does not albumin-correct calcium and is not medical advice.

## Inputs

- **Value** (number): The total calcium value to convert (not albumin-corrected).
- **Source Unit** (select): The unit of the input value.
- **Target Unit** (select): The unit to convert into.
- **Decimal Places** (number)

## When to use

- Convert a laboratory calcium result from mg/dL to mmol/L for SI-unit reporting.
- Convert a calcium result from mmol/L to mg/dL when reviewing conventional lab units.
- Standardize total calcium values for lab medicine, endocrinology, or clinical documentation.

## How it works

- Enter the measured total calcium value.
- Select the source unit: mg/dL or mmol/L.
- Select the target unit: mg/dL or mmol/L.
- Choose between 0 and 8 decimal places, then review the converted result and metadata.

## Use cases

- Translate calcium results between conventional and SI units when comparing laboratory reports.
- Prepare total calcium values for clinical notes, research records, or endocrine documentation.
- Quickly check whether a reported calcium value has been converted correctly.

## Frequently asked questions

### What calcium units does this converter support?

It converts total serum calcium between mg/dL and mmol/L.

### What conversion factor is used?

The conversion from mg/dL to mmol/L uses 0.25. The inverse conversion divides by 0.25, equivalent to multiplying by 4.0.

### Does this tool correct calcium for albumin?

No. It converts the measured total calcium value only and does not perform albumin correction.

### How many decimal places can I choose?

You can select from 0 to 8 decimal places. The default is 2.

### Is this calcium converter medical advice?

No. Use the result as a unit conversion and consult a qualified healthcare professional for interpretation.

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