Interactive Bloch sphere
The Bloch sphere is the most natural way to picture a single qubit. Tap a gate. Measure on any axis. Drag the sphere to rotate the view.
x
0
y
0
z
1.00
|ψ⟩ = (1.00+0i) |0⟩ + (0+0i) |1⟩
Set state
Apply gate
Measure
Set
Pick a starting state from the six axis poles: |0⟩, |1⟩, |+⟩, |−⟩, |+i⟩, |−i⟩.
Gate
Apply Hadamard (H), the Pauli gates (X, Y, Z), or the phase gates (S, S†, T, T†). Watch the state vector rotate.
Measure
Pick an axis to measure on, either Z, X, or Y. The state collapses to one of the two opposite poles, with probability set by where the vector currently points.
New to this?
Read the full guide: What is the Bloch sphere?
Plain-English walkthrough of what the sphere represents, how to read it, and how single-qubit gates and measurements work, with more interactive figures.