# Glucose Unit Converter

> Converts blood glucose between mg/dL (US) and mmol/L (SI) using the molar mass of glucose (1 mmol/L = 18.016 mg/dL, i.e. mg/dL × 0.0555).

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

## Purpose

Converts blood glucose between mg/dL (US) and mmol/L (SI) using the molar mass of glucose (1 mmol/L = 18.016 mg/dL, i.e. mg/dL × 0.0555).

**Use when:** A glucose reading, target or threshold is in the other unit system.

**Do not use when:** You need average glucose from A1C (use a1c-to-glucose) or a different analyte such as cholesterol (use cholesterol-unit-conversion).

## Input

| Parameter | Type | Unit | Required | Description |
| --- | --- | --- | --- | --- |
| `value` | number |  | required | The glucose reading to convert. (> 0, max 5000) |
| `from_unit` | enum: mg_dl \| mmol_l |  | required | Unit of the entered value. |

## Output

| Field | Type | Unit | Description |
| --- | --- | --- | --- |
| `mg_dl` | number | mg/dL | Value in mg/dL. |
| `mmol_l` | number | mmol/L | Value in mmol/L. |
| `conversion` | string |  | The factor used. |

## Formula

`mmol_l = mg_dl × 0.0555; mg_dl = mmol_l / 0.0555 (= mmol_l × 18.016, from the molar mass of glucose 180.16 g/mol)`

The factor 0.0555 is the rounded reciprocal of 18.016; using 18 instead changes results by less than 0.1%. Results are informational only and not a substitute for clinical judgement or medical advice.

## Data Sources

- American Diabetes Association – Diagnosis (A1C, fasting and OGTT thresholds) — https://diabetes.org/about-diabetes/diagnosis (standard, retrieved 2026-09-24)
- Wikipedia – Blood sugar level (unit conversion) — https://en.wikipedia.org/wiki/Blood_sugar_level (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/glucose-unit-conversion?value=…&from_unit=…`
- `POST https://tttkmbb.com/api/v1/calculate/glucose-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/glucose-unit-conversion · OpenAPI operationId `convert_glucose_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": "glucose-unit-conversion", "inputs": {…}}`

## Example

- 100 mg/dL to mmol/L: inputs `{"value":100,"from_unit":"mg_dl"}` → `{"mmol_l":5.55,"mg_dl":100}`
- 7.8 mmol/L to mg/dL: inputs `{"value":7.8,"from_unit":"mmol_l"}` → `{"mg_dl":140.5,"mmol_l":7.8}`

```
GET https://tttkmbb.com/api/v1/calculate/glucose-unit-conversion?value=100&from_unit=mg_dl
```

## Limitations

You need average glucose from A1C (use a1c-to-glucose) or a different analyte such as cholesterol (use cholesterol-unit-conversion). The factor 0.0555 is the rounded reciprocal of 18.016; using 18 instead changes results by less than 0.1%. 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

**Which countries use which unit?**

mg/dL is standard in the US, Germany, Austria, France, Japan and India; mmol/L in the UK, Canada, Australia, China and most of Europe.

**What are the ADA diagnostic thresholds in both units?**

Fasting: 100–125 mg/dL (5.6–6.9 mmol/L) prediabetes, ≥126 mg/dL (7.0 mmol/L) diabetes; 2-hour OGTT ≥200 mg/dL (11.1 mmol/L) diabetes.

## Related

- [A1C to Average Glucose Calculator](https://tttkmbb.com/medical/a1c-to-glucose.md) — Convert A1C to average glucose.
- [Cholesterol Unit Converter](https://tttkmbb.com/medical/cholesterol-unit-conversion.md) — Lipid units use different factors.