# BackendProperties

`qiskit.providers.models.BackendProperties(backend_name, backend_version, last_update_date, qubits, gates, general, **kwargs)`

Bases: `object`

(opens in a new tab)

Class representing backend properties

This holds backend properties measured by the provider. All properties which are provided optionally. These properties may describe qubits, gates, or other general properties of the backend.

Initialize a BackendProperties instance.

**Parameters**

**backend_name**(*str*(opens in a new tab)) – Backend name.**backend_version**(*str*(opens in a new tab)) – Backend version in the form X.Y.Z.**last_update_date**(*datetime.datetime*(opens in a new tab)*or**str*(opens in a new tab)) – Last date/time that a property was updated. If specified as a`str`

, it must be in ISO format.**qubits**(*list*(opens in a new tab)) – System qubit parameters as a list of lists of`Nduv`

objects**gates**(*list*(opens in a new tab)) – System gate parameters as a list of`GateProperties`

objects**general**(*list*(opens in a new tab)) – General parameters as a list of`Nduv`

objects**kwargs**– optional additional fields

## Methods

### faulty_gates

`faulty_gates()`

Return a list of faulty gates.

### faulty_qubits

`faulty_qubits()`

Return a list of faulty qubits.

### frequency

`frequency(qubit)`

Return the frequency of the given qubit.

**Parameters**

**qubit** (*int* (opens in a new tab)) – Qubit for which to return frequency of.

**Returns**

Frequency of the given qubit.

**Return type**

### from_dict

`classmethod from_dict(data)`

Create a new BackendProperties object from a dictionary.

**Parameters**

**data** (*dict* (opens in a new tab)) – A dictionary representing the BackendProperties to create. It will be in the same format as output by `to_dict()`

.

**Returns**

The BackendProperties from the input dictionary.

**Return type**

### gate_error

`gate_error(gate, qubits)`

Return gate error estimates from backend properties.

**Parameters**

**gate**(*str*(opens in a new tab)) – The gate for which to get the error.**qubits**(*int*(opens in a new tab)*|**Iterable*(opens in a new tab)*[**int*(opens in a new tab)*]*) – The specific qubits for the gate.

**Returns**

Gate error of the given gate and qubit(s).

**Return type**

### gate_length

`gate_length(gate, qubits)`

Return the duration of the gate in units of seconds.

**Parameters**

**gate**(*str*(opens in a new tab)) – The gate for which to get the duration.**qubits**(*int*(opens in a new tab)*|**Iterable*(opens in a new tab)*[**int*(opens in a new tab)*]*) – The specific qubits for the gate.

**Returns**

Gate length of the given gate and qubit(s).

**Return type**

### gate_property

`gate_property(gate, qubits=None, name=None)`

Return the property of the given gate.

**Parameters**

**gate**(*str*(opens in a new tab)) – Name of the gate.**qubits**(*int*(opens in a new tab)*|**Iterable*(opens in a new tab)*[**int*(opens in a new tab)*] | None*) – The qubit to find the property for.**name**(*str*(opens in a new tab)*| None*) – Optionally used to specify which gate property to return.

**Returns**

Gate property as a tuple of the value and the time it was measured.

**Raises**

**BackendPropertyError** – If the property is not found or name is specified but qubit is not.

**Return type**

*Tuple* (opens in a new tab)[*Any* (opens in a new tab), *datetime* (opens in a new tab)]

### is_gate_operational

`is_gate_operational(gate, qubits=None)`

Return the operational status of the given gate.

**Parameters**

**gate**(*str*(opens in a new tab)) – Name of the gate.**qubits**(*int*(opens in a new tab)*|**Iterable*(opens in a new tab)*[**int*(opens in a new tab)*] | None*) – The qubit to find the operational status for.

**Returns**

Operational status of the given gate. True if the gate is operational, False otherwise.

**Return type**

### is_qubit_operational

`is_qubit_operational(qubit)`

Return the operational status of the given qubit.

**Parameters**

**qubit** (*int* (opens in a new tab)) – Qubit for which to return operational status of.

**Returns**

Operational status of the given qubit.

**Return type**

### qubit_property

`qubit_property(qubit, name=None)`

Return the property of the given qubit.

**Parameters**

**qubit**(*int*(opens in a new tab)) – The property to look for.**name**(*str*(opens in a new tab)*| None*) – Optionally used to specify within the hierarchy which property to return.

**Returns**

Qubit property as a tuple of the value and the time it was measured.

**Raises**

**BackendPropertyError** – If the property is not found.

**Return type**

*Tuple* (opens in a new tab)[*Any* (opens in a new tab), *datetime* (opens in a new tab)]

### readout_error

`readout_error(qubit)`

Return the readout error of the given qubit.

**Parameters**

**qubit** (*int* (opens in a new tab)) – Qubit for which to return the readout error of.

**Returns**

Readout error of the given qubit.

**Return type**

### readout_length

`readout_length(qubit)`

Return the readout length [sec] of the given qubit.

**Parameters**

**qubit** (*int* (opens in a new tab)) – Qubit for which to return the readout length of.

**Returns**

Readout length of the given qubit.

**Return type**

### t1

`t1(qubit)`

Return the T1 time of the given qubit.

**Parameters**

**qubit** (*int* (opens in a new tab)) – Qubit for which to return the T1 time of.

**Returns**

T1 time of the given qubit.

**Return type**

### t2

`t2(qubit)`

Return the T2 time of the given qubit.

**Parameters**

**qubit** (*int* (opens in a new tab)) – Qubit for which to return the T2 time of.

**Returns**

T2 time of the given qubit.

**Return type**

### to_dict

`to_dict()`

Return a dictionary format representation of the BackendProperties.

**Returns**

The dictionary form of the BackendProperties.

**Return type**