Convert Megawatts to Horsepower - Power Converter
This converter converts power values from megawatts (MW) to horsepower (hp). A megawatt is an SI-derived unit equal to one million watts. Horsepower is a non-SI unit with several variants; by default this tool uses mechanical (imperial) horsepower unless an alternative is specified in surrounding UI.
Use this conversion for quick engineering estimates, reporting, or documentation. When supplying values to regulators, procurement documents, or safety reports, confirm which horsepower definition your audience requires and follow the precision and rounding rules specified by relevant standards.
Governance
Record 17f82fbc36aa • Reviewed by Fidamen Standards Committee
Interactive Converter
Convert between megawatt and horsepower with precision rounding.
Quick reference table
| Megawatt | Horsepower |
|---|---|
| 1 MW | 1,341.022 hp |
| 5 MW | 6,705.109 hp |
| 10 MW | 13,410.219 hp |
| 25 MW | 33,525.546 hp |
| 50 MW | 67,051.093 hp |
| 100 MW | 134,102.186 hp |
Methodology
The conversion is based on the fixed relationship between watts and the selected horsepower definition. 1 watt is the SI base unit of power. Mechanical (imperial) horsepower is defined as 745.699872 watts. Metric horsepower (often labelled PS) is defined as 735.49875 watts.
This converter applies exact multiplicative relationships between units (no iterative or empirical methods). Results are computed from the watt equivalence and then scaled by 1,000,000 to convert megawatts to watts before dividing by the chosen horsepower watt value.
For authoritative unit definitions and guidance on unit presentation and precision, consult the SI and standards bodies listed in citations. For workplace safety and machine-rating contexts, follow applicable occupational and electrical safety standards.
Worked examples
1 MW → mechanical horsepower: 1 × 1,000,000 / 745.699872 = 1341.02209 hp (mechanical).
0.5 MW → mechanical horsepower: 0.5 × 1,000,000 / 745.699872 = 670.51105 hp (mechanical).
2.5 MW → metric horsepower (PS): 2.5 × 1,000,000 / 735.49875 = 3400.62003 hp (PS).
F.A.Q.
Which horsepower definition does this converter use by default?
By default the conversion is presented against mechanical (imperial) horsepower, defined as 745.699872 W. If your application requires metric horsepower (PS) or another variant, use the alternate formula or select the appropriate unit in the UI.
How many significant digits are reasonable?
For engineering estimates 3 to 5 significant digits are common. When producing regulatory or procurement figures, follow the precision and rounding conventions specified by the receiving authority or the cited standards. Always state the horsepower definition and number of significant digits used.
Can rounding or unit choice affect safety or compliance?
Yes. For machine ratings, electrical equipment specifications, or compliance documentation, use the exact unit definition and rounding rules required by the standard or regulator. Small differences between horsepower variants can matter when close to rating thresholds.
Why does metric horsepower (PS) give a different number than mechanical horsepower?
Different historical definitions set horsepower to slightly different watt equivalents. Mechanical (imperial) horsepower is 745.699872 W while metric horsepower (PS) is 735.49875 W, producing different numeric results for the same megawatt input.
Are these conversions suitable for billing or legal contracts?
For billing, contracts, or legal documents, confirm the required unit definitions and rounding rules with the counterparty and reference applicable standards. Where necessary, include a note about the definition used and link to the referenced standard.
How accurate is the conversion here?
The calculation uses the exact watt-equivalents for the chosen horsepower definitions. Displayed precision may be limited by the UI. For traceable measurement and calibration needs, follow guidelines from metrology authorities and calibrate instruments according to standards such as those referenced below.
Sources & citations
- NIST - Metric System and SI Units guidance — https://www.nist.gov/pml/weights-and-measures/metric-si
- ISO - Quantities and units (ISO standards catalogue) — https://www.iso.org/standards.html
- IEEE Standards Association — https://standards.ieee.org
- OSHA - U.S. Occupational Safety and Health Administration — https://www.osha.gov
- BIPM - SI Brochure (International system of units) — https://www.bipm.org/en/publications/si-brochure
- ISO 80000-4:2019 — Mechanics — https://www.iso.org/standard/64975.html
- NIST SP 811 — Guide for the Use of the International System of Units — https://www.nist.gov/pml/special-publication-811
Further resources
Related tools
External guidance
Versioning & Change Control
Audit record (versions, QA runs, reviewer sign-off, and evidence).
Record ID: 17f82fbc36aaWhat changed (latest)
v1.0.0 • 2025-11-10 • MINOR
Initial publication and governance baseline.
Why: Published with reviewed formulas, unit definitions, and UX controls.
Public QA status
PASS — golden 25 + edge 120
Last run: 2026-01-23 • Run: golden-edge-2026-01-23
Versioning & Change Control
Audit record (versions, QA runs, reviewer sign-off, and evidence).
What changed (latest)
v1.0.0 • 2025-11-10 • MINOR
Initial publication and governance baseline.
Why: Published with reviewed formulas, unit definitions, and UX controls.
Public QA status
PASS — golden 25 + edge 120
Last run: 2026-01-23 • Run: golden-edge-2026-01-23
Engine
v1.0.0
Data
Baseline (no external datasets)
Content
v1.0.0
UI
v1.0.0
Governance
Last updated: Nov 10, 2025
Reviewed by: Fidamen Standards Committee (Review board)
Credentials: Internal QA
Risk level: low
Reviewer profile (entity)
Fidamen Standards Committee
Review board
Internal QA
Entity ID: https://fidamen.com/reviewers/fidamen-standards-committee#person
Semantic versioning
- MAJOR: Calculation outputs can change for the same inputs (formula, rounding policy, assumptions).
- MINOR: New features or fields that do not change existing outputs for the same inputs.
- PATCH: Bug fixes, copy edits, or accessibility changes that do not change intended outputs except for previously incorrect cases.
Review protocol
- Verify formulas and unit definitions against primary standards or datasets.
- Run golden-case regression suite and edge-case suite.
- Record reviewer sign-off with credentials and scope.
- Document assumptions, limitations, and jurisdiction applicability.
Assumptions & limitations
- Uses exact unit definitions from the Fidamen conversion library.
- Internal calculations use double precision; display rounding follows the unit's configured decimal places.
- Not a substitute for calibrated instruments in regulated contexts.
- Jurisdiction-specific rules may require official guidance.
Change log
v1.0.0 • 2025-11-10 • MINOR
Initial publication and governance baseline.
Why: Published with reviewed formulas, unit definitions, and UX controls.
Areas: engine, content, ui • Reviewer: Fidamen Standards Committee • Entry ID: 8e6933bc97e3