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Physics calculator

Efficiency Calculator

Power efficiency η=Pout/Pin as fraction and percent. Runs locally in your browser.

Instant result
Result
—

Enter values to calculate.

Inputs—
Mode—
Formula—
Trust summary CVP VERIFIED · CVP protocol 1.0.0-proposed · Engineering assurance
Input interpretation
Enter values to calculate.
Result
—
Assurance
Engineering
Declared partition coverage
PASS · 2/2 declared partitions (efficiency, invalid-domain) · Matrix
Known limitations
  • Power ratio; no energy gain
  • Core CVP does not include live graph, viewport, or pointer interaction.
Model
η = Pout / Pin
Scope
Documented on page
Verification
Engine tested · Source checked · v1.0.0 · CVP VERIFIED · CVP protocol 1.0.0-proposed · Engineering assurance· View Manifest · CVP overview · Specification
Versions
Calculation 1.0.0 · CVP protocol 1.0.0-proposed
CVP identity
1/1 property · digest 2b795fc90237
Legacy regression
3/3 tests · Production surface contract 4/4
Reference
O1 model · O2 expected_values · O2 numerical_behavior
Interfaces
PASS · UI (SSR) / REST / MCP — ui-ssr is query-result HTML, not a live browser session.
Supplemental domain review
Internal · Pass
Named expert review
Not performed
CVP suite
1/1 golden · 1/1 CVP boundary · 1/1 invalid · 1/1 property · 1/1 cross-interface · 1/1 CVP contract · Manifest
Sources
  • Intro physics / NIST units — standard relations
  • ISO 80000-5 — Thermodynamics / energy — Efficiency
Sources
Evidence
1 legacy golden · 1 legacy boundary · legacy regression suite · 1/1 oracle-backed golden · 1/1 invalid · Artifact integrity PASS · CalculatorX electrical review
This calculator CURRENT · Public schema 1.0.0 matches · Semantic contract ✓ · Production attested · Public/cache ✓ · Origin ✓
Semantic contract
PASS
Full verification

Manifest identity, reference classes, interfaces, suite, and production records.

Formulas

Core equations used by this calculator.

Efficiencyη = Pout / Pin
Percentη% = 100 · η
iSI units unless noted.

How to use

1

Enter output power and input power

Both must be greater than zero for a meaningful efficiency.

2

Confirm units match

Use the same power unit for Pin and Pout (W, kW, etc.).

3

Read efficiency

η = Pout / Pin, also shown as a percent when applicable.

Example calculations

Common configurations with formula and result.

ϟ

Example

validation

—
Pin=100 W, Pout=85 W → η=0.85 (85%)

Efficiency calculator specification

Version 1.0.0 · Engine tested · Supplemental domain review · Internal · 2026-08-09

Calculation status

Review policy · Evidence · Reviewed by CalculatorX electrical review

Definition
η = Pout / Pin
What it calculates
η = Pout / Pin
Inputs
  • see form
Outputs
  • see API
Formula
see formulas
Assumptions
  • Documented on page
Units
  • SI
Boundary conditions
  • coded hard errors
Example
Pin=100 W, Pout=85 W → η=0.85 (85%)
Validation cases

1 published on this page · 3/3 tests · Production surface contract 4/4 · View evidence

  • see suite → see suite
Sources
  • Intro physics / NIST units — standard relations
    Supports: engine formulas
  • ISO 80000-5 — Thermodynamics / energy — Efficiency
    Supports: η = Pout/Pin ≤ 1
Last reviewed
2026-08-09
Reviewed by
CalculatorX electrical review
Calculation version
1.0.0

Background

Interpretation and common distinctions.

η = Pout / Pin

Supported and not supported

Supported — API physics.energy.efficiency

Not supported — Carnot limits, exergy analysis

Agent / API notes

Capability id: physics.energy.efficiency · tool id: efficiency · pin 1.0.0.

Other calculators in this family: Work and Power, Watt ↔ HP .

W Work and Power › P Watt ↔ HP ›
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Frequently asked questions

Key distinctions behind the calculation.

What does the API reject?

Hard validation errors such as missing inputs or out-of-range values.