VSWR & Return Loss Calculator

Compute voltage standing wave ratio (VSWR), the reflection coefficient Γ, return loss, and mismatch loss for an RF load. Enter the load impedance (R + jX) and a reference impedance to get Γ and VSWR; or enter forward and reflected power; or start from a VSWR value. Pairs with the Decibel Calculator for RF link budgets. Everything runs locally in your browser.

Load R Ω Load jX Ω Reference Z₀ Ω

Reflection coefficient Γ = (Z_L − Z₀) / (Z_L + Z₀) (complex, with Z_L = R + jX). VSWR = (1 + |Γ|) / (1 − |Γ|). Return loss = −20·log₁₀|Γ| dB. Mismatch loss = −10·log₁₀(1 − |Γ|²) dB — the transmission lost to reflection. From power: |Γ|² = P_refl / P_fwd. A perfect match is |Γ| = 0, VSWR = 1, infinite return loss. Everything runs locally — nothing leaves your browser.