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 — 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.