Manage circuit files

Overview

Circuit Composer is a graphical interface on which to build quantum circuits and run them on a simulator or real quantum hardware.

You can build circuits in two ways:

  • Drag and drop gates and other operations.

  • Enter or import OpenQASM code.

Open Circuit Composer

  1. Open Circuit Composer by clicking the circuit icon on the left-hand navigation of IBM Quantum Experience.

  2. (Optional) If you are not currently signed in to IBM Quantum Experience, click Sign in in the upper right corner. Then, you can either sign in or Create an IBMid account. If you don’t sign in, the visualizations at the bottom of the page automatically show simulated results for up to four qubits. However, if you want to run your circuit on a simulator backend or on real quantum hardware, you must sign in.

On the Circuit Composer page, you will see several windows:

You can also access your list of saved circuits from this page.

Code editor, Docs, or Jobs window

By default, the code editor shows in this window, with editable OpenQASM code, but you can use the dropdown to show read-only Python code instead. By clicking the menu in the right corner of the code editor, OpenQASM code can be copied, imported, or exported. Python code can be copied or exported. Click the Open in Quantum Lab button in the lower left corner to open Python code in a notebook in Quantum Lab.

The code editor generates OpenQASM or Python code based on changes made in the graphical editor. Additionally, if you edit the OpenQASM code, changes are reflected in the graphical editor.

For instructions to create circuits with OpenQASM code, see Build your circuit with OpenQASM code.

Use the Docs tab to view links to commonly used topics.

Open the Jobs tab for a list of all of your current and past jobs. You must be signed in to view this list.

You can click the name of the open tab to close this window.

Graphical editor

Use the graphical editor to create circuits by dragging and dropping operations. Read more about how to create circuits by dragging and dropping in the Build your circuit with drag-and-drop section.

Operations List

This bar lists all of the operations available for use in the graphical editor. For details about each operation, see Operations glossary.

Visualizations

The visualizations windows help you visualize your circuit. By default, the Measurement probabilities and Q-sphere windows are open, but you can also open the Statevector visualization window by selecting it in the View menu. For details about the types of available visualizations, see Visualizations.

Note

The visualizations are from a single-shot statevector simulator. This is different from the backend specified in the Run settings, which is the backend that runs your circuit once you click the Run button.

List of saved circuits

If you are signed in, you can click the file icon to the left of the circuit name to access the list of your saved circuits. This list includes four columns:

  • Name (you assign a name when you save your circuit)

  • Description (optional)

  • Updated (dated and time the circuit was last saved)

  • ID (an identifying number assigned by the system)

Click a circuit’s name to open that circuit in Circuit Composer.

Select the box by a circuit name to rename or delete the circuit, or to export the OpenQASM file. You can delete or export multiple circuits at the same time.

List of saved circuits, showing a selected circuit and the Export OpenQASM / Rename / Delete buttons