# Cholesterol Unit Converter

> Converts total, HDL, LDL or non-HDL cholesterol (factor 0.02586) and triglycerides (factor 0.01129) between mg/dL and mmol/L.

- Calculator id: `cholesterol-unit-conversion` · Category: Medical & Clinical (`medical`) · Tool name: `convert_cholesterol_units`
- Canonical page: https://tttkmbb.com/medical/cholesterol-unit-conversion · This document: https://tttkmbb.com/medical/cholesterol-unit-conversion.md · JSON definition: https://tttkmbb.com/medical/cholesterol-unit-conversion.json

## Purpose

Converts total, HDL, LDL or non-HDL cholesterol (factor 0.02586) and triglycerides (factor 0.01129) between mg/dL and mmol/L.

**Use when:** A lipid result or target is reported in the other unit system.

**Do not use when:** You need to calculate LDL from a lipid panel (use ldl-cholesterol) or convert glucose (use glucose-unit-conversion), which use different factors.

## Input

| Parameter | Type | Unit | Required | Description |
| --- | --- | --- | --- | --- |
| `value` | number |  | required | The lipid value to convert. (> 0, max 10000) |
| `from_unit` | enum: mg_dl \| mmol_l |  | required | Unit of the entered value. |
| `analyte` | enum: total_cholesterol \| hdl \| ldl \| non_hdl \| triglycerides |  | optional, default "total_cholesterol" | Cholesterol fractions share one factor; triglycerides use another. |

## Output

| Field | Type | Unit | Description |
| --- | --- | --- | --- |
| `mg_dl` | number | mg/dL | Value in mg/dL. |
| `mmol_l` | number | mmol/L | Value in mmol/L. |
| `factor` | number |  | 0.02586 for cholesterol, 0.01129 for triglycerides. |
| `analyte` | string |  | Analyte converted. |

## Formula

`cholesterol: mmol_l = mg_dl × 0.02586 (molar mass 386.65 g/mol); triglycerides: mmol_l = mg_dl × 0.01129 (average molar mass ≈ 885 g/mol); reverse: mg_dl = mmol_l / factor`

The triglyceride factor depends on an assumed average molecular weight, so laboratories may differ by about 1%. Results are informational only and not a substitute for clinical judgement or medical advice.

## Data Sources

- American Heart Association – What your cholesterol levels mean — https://www.heart.org/en/health-topics/cholesterol/about-cholesterol/what-your-cholesterol-levels-mean (reference, retrieved 2026-09-24)
- Wikipedia – Cholesterol (units and reference ranges) — https://en.wikipedia.org/wiki/Cholesterol (reference, retrieved 2026-09-24)

Data freshness: `static`. Deterministic formula with fixed constants; results never go stale. Inputs supplied by the caller determine the output.

## API

- `GET https://tttkmbb.com/api/v1/calculate/cholesterol-unit-conversion?value=…&from_unit=…`
- `POST https://tttkmbb.com/api/v1/calculate/cholesterol-unit-conversion` with JSON body `{"inputs": {…}}`
- Response: unified envelope (`success`, `request`, `result.values`, `result.units`, `sources`, `freshness`, `timestamp`, `next_actions`, `links`); see https://tttkmbb.com/docs/response-format.md
- Schema: https://tttkmbb.com/api/v1/calculators/cholesterol-unit-conversion · OpenAPI operationId `convert_cholesterol_units` in https://tttkmbb.com/openapi.json
- Authentication: none. Rate limit: fair use, see https://tttkmbb.com/docs/rate-limits.md.

## MCP

- Server: `https://tttkmbb.com/mcp` (Streamable HTTP, JSON-RPC 2.0, no auth)
- Tool:  `run_calculator` with `{"calculator_id": "cholesterol-unit-conversion", "inputs": {…}}`

## Example

- Total cholesterol 200 mg/dL: inputs `{"value":200,"from_unit":"mg_dl","analyte":"total_cholesterol"}` → `{"mmol_l":5.17,"factor":0.02586}`
- Triglycerides 150 mg/dL: inputs `{"value":150,"from_unit":"mg_dl","analyte":"triglycerides"}` → `{"mmol_l":1.69,"factor":0.01129}`
- LDL 3.0 mmol/L: inputs `{"value":3,"from_unit":"mmol_l","analyte":"ldl"}` → `{"mg_dl":116}`

```
GET https://tttkmbb.com/api/v1/calculate/cholesterol-unit-conversion?value=200&from_unit=mg_dl&analyte=total_cholesterol
```

## Limitations

You need to calculate LDL from a lipid panel (use ldl-cholesterol) or convert glucose (use glucose-unit-conversion), which use different factors. The triglyceride factor depends on an assumed average molecular weight, so laboratories may differ by about 1%. Results are informational only and not a substitute for clinical judgement or medical advice. All values are computed from the formula above; no measurement or live data is involved.

## FAQ

**Why do triglycerides use a different factor?**

They are a different molecule (about 885 g/mol versus 386.65 g/mol for cholesterol), so 1 mmol/L of triglycerides is about 88.5 mg/dL while 1 mmol/L of cholesterol is 38.67 mg/dL.

**What are common targets in both units?**

LDL below 100 mg/dL is 2.6 mmol/L, below 70 mg/dL is 1.8 mmol/L; triglycerides below 150 mg/dL is 1.7 mmol/L.

## Related

- [LDL Cholesterol Calculator](https://tttkmbb.com/medical/ldl-cholesterol.md) — Calculate LDL and non-HDL from a lipid panel.
- [Glucose Unit Converter](https://tttkmbb.com/medical/glucose-unit-conversion.md) — Glucose uses a different factor.