Skip to main content
Calcimator

Quantum Measurement Calculator

Calculate quantum measurement probabilities, expectation values, variance, and wave function collapse.

Inputs

Results

Outcome 1 Probability

50%

Outcome 2 Probability

50%

Expectation Value

0

Variance1
Standard Deviation1
Measurement Fidelity0.5
How to Use This Calculator
  1. Enter State 1 Amplitude and State 2 Amplitude — they should satisfy |α₁|² + |α₂|² = 1 for a valid normalized state.
  2. Choose Measurement Basis: Computational Basis (|0⟩, |1⟩) for standard qubit readout, Hadamard Basis (+/−) for X-basis measurement.
  3. Read Outcome 1 Probability and Outcome 2 Probability — these are the Born rule probabilities for each measurement result.
  4. The Expectation Value is the average of many identical measurements; Variance shows how spread out results will be.
  5. Measurement Fidelity indicates how faithfully the measurement distinguishes the two outcomes.
Ad Placeholder

Formula

P(outcome) = |⟨outcome|ψ⟩|²

Related Calculators

Ad Placeholder