---
title: "Get the Most Recent Backend Characterization"
method: GET
path: "/characterizations/backends/{backend}/current"
tags: ["characterizations"]
---

# Get the Most Recent Backend Characterization

`GET /characterizations/backends/{backend}/current`

This endpoint retrieves the most recent backend characterization data available.

## Path parameters

- `backend` 'qpu.aria-1' | 'qpu.aria-2' | 'qpu.forte-1' | 'qpu.forte-enterprise-1', required

## Response `200`

Successfully retrieved current characterization

- Characterization — Quantum hardware characterization data.
  - `backend` string — The backend calibrated hardware: `simulator`, `qpu.aria-1`, `qpu.aria-2`, `qpu.forte-1`, `qpu.forte-enterprise-1`
  - `connectivity` array[] — An array of valid, unordered tuples of possible qubits for executing two-qubit gates (e.g., `[[0, 1], [0, 2], [1, 2]]`)
    - integer[]
  - `date` string — Date time of the measurement, in ISO format.
  - `fidelity` object — Fidelity for single-qubit (`1q`) and two-qubit (`2q`) gates, and State Preparation and Measurement (`spam`) operations. Currently provides only median fidelity; additional statistical data will be added in the future.
    - `spam` object, required — SPAM error correction information.
      - `median` number, required
      - `stderr` integer — SPAM error.
  - `id` string, uuid — UUID of the characterization.
  - `qubits` integer — The number of qubits available.
  - `timing` object — Time, in seconds, of various system properties: `t1` time, `t2` time, `1q` gate time, `2q` gate time, `readout` time, and qubit `reset` time.
    - `1q` integer
    - `2q` integer
    - `readout` integer, required — Readout time.
    - `reset` integer, required — qubit reset time.
    - `t1` integer
    - `t2` integer

---

[API](https://skmtc.net/ionq/apis/ionq-cloud-platform-api.md) · [All operations](https://skmtc.net/ionq/apis/ionq-cloud-platform-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/ionq/ionq-cloud-platform-api/versions/0410071e1cd0/schema)