# Millimeters of mercury to Kilopascals (mmHg to kPa)

> Convert millimeters of mercury to kilopascals: 1 mmHg = 0.133322 kPa. Exact conversion factor, formula, 22-row table and worked examples, with JSON API and MCP access.

- Page id: `mmhg-to-kpa` · Quantity: Pressure (`pressure`, base unit Pa) · Tool: `convert_units`
- Canonical page: https://tttkmbb.com/conversion/mmhg-to-kpa · This document: https://tttkmbb.com/conversion/mmhg-to-kpa.md · JSON: https://tttkmbb.com/conversion/mmhg-to-kpa.json (add `?value=` for a result)

## Formula

- `1 mmHg = 0.133322 kPa`
- `kilopascals = millimeters of mercury × 0.1333223874`
- Reverse: `millimeters of mercury = kilopascals × 7.500615758`

The factor follows from the SI definitions of both units (NIST SP 811); values below are rounded to 6 significant figures, the API returns up to 12.

## Worked examples

- 5 mmHg = 0.666612 kPa
- 12.5 mmHg = 1.66653 kPa
- 100 mmHg = 13.3322 kPa

## Conversion table

| Millimeters of mercury (mmHg) | Kilopascals (kPa) |
| --- | --- |
| 1 | 0.133322 |
| 2 | 0.266645 |
| 3 | 0.399967 |
| 4 | 0.53329 |
| 5 | 0.666612 |
| 6 | 0.799934 |
| 7 | 0.933257 |
| 8 | 1.06658 |
| 9 | 1.1999 |
| 10 | 1.33322 |
| 15 | 1.99984 |
| 20 | 2.66645 |
| 25 | 3.33306 |
| 30 | 3.99967 |
| 40 | 5.3329 |
| 50 | 6.66612 |
| 75 | 9.99918 |
| 100 | 13.3322 |
| 200 | 26.6645 |
| 250 | 33.3306 |
| 500 | 66.6612 |
| 1000 | 133.322 |

## API

- `GET https://tttkmbb.com/api/v1/convert?value=5&from_unit=mmHg&to_unit=kPa` → unified JSON envelope with `result.values.result`, `formula`, `factor`, `sources`, `freshness`
- MCP: server `https://tttkmbb.com/mcp`, tool `convert_units` with `{"value":5,"from_unit":"mmHg","to_unit":"kPa"}`
- All pressure units: https://tttkmbb.com/api/v1/units?quantity=pressure · full converter: [Pressure Converter](https://tttkmbb.com/conversion/pressure.md)
- Authentication: none. Freshness: `static` (fixed conversion factors).

## FAQ

**How many kilopascals are in one millimeter of mercury?**

1 mmHg = 0.133322 kPa. The factor comes from the SI definitions of both units (NIST SP 811 / BIPM), so it is exact or correct to at least 10 significant figures.

**What is the formula to convert millimeters of mercury to kilopascals?**

Multiply the value in millimeters of mercury by 0.1333223874: kilopascals = millimeters of mercury × 0.1333223874. For example, 5 mmHg = 0.666612 kPa.

**How do I convert kilopascals back to millimeters of mercury?**

Multiply by the inverse factor 7.500615758 (millimeters of mercury = kilopascals × 7.500615758), or use the kilopascals-to-millimeters of mercury page.

## Related conversions

- [Kilopascals to millimeters of mercury](https://tttkmbb.com/conversion/kpa-to-mmhg.md) (reverse)
- [Psi to Bar](https://tttkmbb.com/conversion/psi-to-bar.md)
- [Bar to Psi](https://tttkmbb.com/conversion/bar-to-psi.md)
- [Psi to Kilopascals](https://tttkmbb.com/conversion/psi-to-kpa.md)
- [Kilopascals to Psi](https://tttkmbb.com/conversion/kpa-to-psi.md)
- [Bar to Kilopascals](https://tttkmbb.com/conversion/bar-to-kpa.md)
- [Kilopascals to Bar](https://tttkmbb.com/conversion/kpa-to-bar.md)
- [Atmospheres to Pascals](https://tttkmbb.com/conversion/atm-to-pa.md)
- [Pascals to Atmospheres](https://tttkmbb.com/conversion/pa-to-atm.md)

## Data Sources

- NIST Special Publication 811 – Guide for the Use of the International System of Units (SI), Appendix B conversion factors — https://www.nist.gov/pml/special-publication-811 (standard, retrieved 2026-09-24)
- BIPM – The International System of Units (SI Brochure, 9th edition) — https://www.bipm.org/en/publications/si-brochure (standard, retrieved 2026-09-24)
- Wikipedia – Conversion of units — https://en.wikipedia.org/wiki/Conversion_of_units (reference, retrieved 2026-09-24)