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Electrical calculator

VSWR Calculator

Convert between reflection coefficient |Γ|, VSWR, and return loss. 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 · 3/3 declared partitions (from-gamma, from-vswr, invalid-domain) · Matrix
Known limitations
  • Scalar |Γ| only — no complex Γ
  • Core CVP does not include live graph, viewport, or pointer interaction.
Model
|Γ| ↔ VSWR ↔ return loss (+ mismatch loss).
Scope
Scalar magnitude model
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
2/2 property · digest 9cf34900f188
Legacy regression
6/6 tests · Production surface contract 3/3
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 · electrical-engineer
Named expert review
Not performed
CVP suite
3/3 golden · 2/2 CVP boundary · 2/2 invalid · 2/2 property · 1/1 cross-interface · 1/1 CVP contract · Manifest
Sources
  • IEEE / microwave engineering references — VSWR and return loss
  • Pozar — Microwave Engineering — Reflection coefficient and standing-wave ratio
Sources
Evidence
2 legacy golden · 2 legacy boundary · legacy regression suite · 3/3 oracle-backed golden · 2/2 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.

VSWRVSWR = (1+|Γ|)/(1−|Γ|)
Return lossRL = −20·log10(|Γ|)
iScalar |Γ| model; not a full S-parameter network.

How to use

1

Choose Γ, VSWR, or return loss input

Enter the quantity you already know.

2

Enter the value

Γ ∈ [0,1), VSWR ≥ 1, or RL_dB ≥ 0 as required by the mode.

3

Read the related match metrics

VSWR = (1+|Γ|)/(1−|Γ|); RL relates to |Γ| as labeled.

Example calculations

Common configurations with formula and result.

ϟ

|Γ|=0.2

gamma mode

VSWR=(1+0.2)/(1−0.2)
VSWR ≈ 1.500 · RL ≈ 13.98 dB

VSWR calculator specification

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

Calculation status

Review policy · Evidence · Reviewed by CalculatorX electrical review (electrical-engineer)

Definition
VSWR = (1+|Γ|)/(1−|Γ|). Return loss RL = −20·log10(|Γ|). Mismatch loss = −10·log10(1−|Γ|²).
What it calculates
|Γ| ↔ VSWR ↔ return loss (+ mismatch loss).
Inputs
  • mode gamma|vswr|rl
  • Gamma ∈ [0,1) or VSWR≥1 or RL_dB≥0
Outputs
  • Gamma
  • VSWR
  • RL_dB
  • mismatch_loss_dB
Formula
VSWR=(1+|Γ|)/(1−|Γ|)
Assumptions
  • Scalar magnitude model
Units
  • —, dB
Boundary conditions
  • |Γ|≥1 → GAMMA_OUT_OF_RANGE
  • Bad mode → INVALID_MODE
Example
Γ=0.2 → VSWR=1.5
Validation cases

1 published on this page · 6/6 tests · Production surface contract 3/3 · View evidence

  • Gamma=0.2 → VSWR≈1.5
Sources
  • IEEE / microwave engineering references — VSWR and return loss
    Supports: Γ↔VSWR↔RL identities
  • Pozar — Microwave Engineering — Reflection coefficient and standing-wave ratio
    Supports: Γ↔VSWR↔RL textbook identities
Last reviewed
2026-08-08
Reviewed by
CalculatorX electrical review (electrical-engineer)
Calculation version
1.0.0

Background

Interpretation and common distinctions.

Convert VSWR, |Γ|, and return loss.

Default: |Γ|=0.2 → VSWR ≈ 1.500.

Agent / API notes

Capability id: electrical.rf.vswr · tool id: vswr · pin 1.0.0.

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Frequently asked questions

Key distinctions behind the calculation.

What VSWR is ideal?

1:1 (Γ=0). Higher VSWR means more reflected power.

|Γ| ≥ 1?

API returns GAMMA_OUT_OF_RANGE — passive matches require |Γ|<1.