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openapi: 3.2.0
info:
title: IonQ Cloud Platform Characterizations API
version: v0.2
description: '*Last updated: October 19, 2026*
# Introduction
Welcome to the IonQ platform! You can use our API and the `qcloud` command-line interface to submit and retrieve jobs on our quantum hardware as well as our high-performance simulator.
Our API uses the REST architectural style; this means we provide unsurprising, resource-oriented URLs and take advantage of built-in HTTP response codes, authentication, verbs, and other features.
We allow cross-site requests from any domain, and return JSON responses.
If you prefer to not think about HTTP, use our OpenAPI spec to generate bindings for your language of choice. Pre-generated bindings for Python and JavaScript are coming soon.
## Non-breaking changes
* Histogram example expanded to include scientific notation for a JSON numeric value.
## Migrating to v0.2
### Breaking changes
* Calibrations endpoints has been deprecated in favor of Characterizations.
### New features
* Ability to specifify target hardware generation on Job creation. e.g. `qpu.harmony` for targeting our 11-qubit system.
* Introduces Characterizations endpoints. Enables fetching current and historic characterizations for specific targets.
* Backends availability and other stats can now be fetched.
## Migrating to v0.1
### Breaking changes
Prerelease version `v0.1` has one major breaking change from `v0`:
* Canceling jobs is now done via a PUT. This allows us to more naturally support job deletion.
### New features
* Completely deleting one or more jobs is now possible
* Multiple jobs may be canceled simultaneously
* A list of jobs may be fetched simultaneously
## API status
API and quantum computer status is continuously reported at https://status.ionq.co/.
Please subscribe for automated updates when we perform maintenance or experience an outage.
In addition, you may use the status endpoint to check the current status of our API.
## Authentication'
contact:
name: IonQ
email: support@ionq.co
url: https://ionq.com/
x-logo:
url: https://static.ionq.co/images/ionq-logo-dark.png
altText: IonQ Logo
href: '#'
servers:
- url: https://api.ionq.co/v0.2
description: Current Endpoint
- url: https://api.ionq.co/v0.1
basePath: /v0.2
security:
- API Key: []
tags:
- name: characterizations
x-displayName: Characterizations
description: 'A **characterization** is a snapshot of the IonQ platform''s performance at a moment in time.
While our computers are continuously calibrated moment to moment, we periodically take measurements of gate fidelities and other statistics.'
paths:
/characterizations/backends/{backend}:
get:
operationId: getCharacterizationsForBackend
summary: Get All Backend Characterizations
description: This endpoint retrieves an array of all available backend characterizations, with pagination.
tags:
- characterizations
parameters:
- name: backend
in: path
required: true
description: A backend where jobs can run on.
schema:
type: string
enum:
- qpu.s11
- name: start
in: query
description: Characterizations starting at this time (e.g., `start=1585713600000`)
schema:
type: integer
- name: end
in: query
description: Characterizations before this time (e.g., `end=1585713600000`)
schema:
type: integer
- name: limit
in: query
description: How many objects to return.
schema:
type: integer
default: 10
minimum: 1
maximum: 10
- name: page
in: query
schema:
type: integer
default: 1
minimum: 1
description: Specify the page of results to return.
responses:
'200':
description: Successfully retrieved characterizations.
content:
application/json:
schema:
type: object
description: Response body from requesting characterization data.
required:
- characterizations
properties:
characterizations:
type: array
description: A page of characterizations measurements.
items:
type: object
description: Quantum hardware characterization data.
properties:
id:
type: string
description: UUID of the characterization.
format: uuid
date:
type: integer
description: Time of the measurement, from Unix epoch in seconds.
target:
type: string
description: The target calibrated hardware.
enum:
- qpu.s11
qubits:
type: integer
description: The number of qubits available.
minimum: 0
connectivity:
type: array
description: An array of valid, unordered tuples of possible qubits for executing two-qubit gates (e.g., `[[0, 1], [0, 2], [1, 2]]`)
example:
- - 0
- 1
- - 0
- 2
- '...'
- - 10
- 9
items:
type: array
items:
type: integer
fidelity:
type: object
description: 'Fidelity for single-qubit (`1q`) and two-qubit (`2q`) gates, and State Preparation and Measurement (`spam`) operations.
Currently provides only mean fidelity; additional statistical data will be added in the future.
'
required:
- spam
properties:
spam:
type: object
description: SPAM error correction information.
required:
- mean
properties:
mean:
type: integer
description: Mean SPAM value.
minimum: 0
stderr:
type: integer
description: SPAM error.
minimum: 0
timing:
type: object
description: 'Time, in seconds, of various system properties: `t1` time, `t2` time, `1q` gate time, `2q` gate time, `readout` time, and qubit `reset` time.'
required:
- readout
- reset
properties:
readout:
type: integer
description: Readout time.
reset:
type: integer
description: qubit reset time.
pages:
type: integer
description: The number of remaining pages of characterization measurements.
x-codeSamples:
- lang: curl
source: "curl \"https://api.ionq.co/v0.2/characterizations/backends/qpu.s11\" \\\n -H \"Authorization: apiKey your-api-key\"\n"
/characterizations/backends/{backend}/current:
get:
operationId: getCharacterizationsCurrentForBackend
summary: Get the Most Recent Backend Characterization
description: This endpoint retrieves the most recent backend characterization data available.
tags:
- characterizations
parameters:
- name: backend
in: path
required: true
description: A backend where jobs can run on.
schema:
type: string
enum:
- qpu.s11
responses:
'200':
description: Successfully retrieved current characterization
content:
application/json:
schema:
type: object
description: Quantum hardware characterization data.
properties:
id:
type: string
description: UUID of the characterization.
format: uuid
date:
type: integer
description: Time of the measurement, from Unix epoch in seconds.
target:
type: string
description: The target calibrated hardware.
enum:
- qpu.s11
qubits:
type: integer
description: The number of qubits available.
minimum: 0
connectivity:
type: array
description: An array of valid, unordered tuples of possible qubits for executing two-qubit gates (e.g., `[[0, 1], [0, 2], [1, 2]]`)
example:
- - 0
- 1
- - 0
- 2
- '...'
- - 10
- 9
items:
type: array
items:
type: integer
fidelity:
type: object
description: 'Fidelity for single-qubit (`1q`) and two-qubit (`2q`) gates, and State Preparation and Measurement (`spam`) operations.
Currently provides only mean fidelity; additional statistical data will be added in the future.
'
required:
- spam
properties:
spam:
type: object
description: SPAM error correction information.
required:
- mean
properties:
mean:
type: integer
description: Mean SPAM value.
minimum: 0
stderr:
type: integer
description: SPAM error.
minimum: 0
timing:
type: object
description: 'Time, in seconds, of various system properties: `t1` time, `t2` time, `1q` gate time, `2q` gate time, `readout` time, and qubit `reset` time.'
required:
- readout
- reset
properties:
readout:
type: integer
description: Readout time.
reset:
type: integer
description: qubit reset time.
x-codeSamples:
- lang: curl
source: "curl \"https://api.ionq.co/v0.2/characterizations/backends/qpu.s11/current\" \\\n -H \"Authorization: apiKey your-api-key\"\n"
/characterizations/{UUID}:
get:
operationId: getCharacterization
summary: Get a Characterization
description: This endpoint retrieves a characterization.
tags:
- characterizations
parameters:
- name: UUID
in: path
required: true
example: 617a1f8b-59d4-435d-aa33-695433d7155e
description: A UUID identifying a specific resource
schema:
type: string
format: uuid
responses:
'200':
description: Successfully retrieved current characterization
content:
application/json:
schema:
type: object
description: Quantum hardware characterization data.
properties:
id:
type: string
description: UUID of the characterization.
format: uuid
date:
type: integer
description: Time of the measurement, from Unix epoch in seconds.
target:
type: string
description: The target calibrated hardware.
enum:
- qpu.s11
qubits:
type: integer
description: The number of qubits available.
minimum: 0
connectivity:
type: array
description: An array of valid, unordered tuples of possible qubits for executing two-qubit gates (e.g., `[[0, 1], [0, 2], [1, 2]]`)
example:
- - 0
- 1
- - 0
- 2
- '...'
- - 10
- 9
items:
type: array
items:
type: integer
fidelity:
type: object
description: 'Fidelity for single-qubit (`1q`) and two-qubit (`2q`) gates, and State Preparation and Measurement (`spam`) operations.
Currently provides only mean fidelity; additional statistical data will be added in the future.
'
required:
- spam
properties:
spam:
type: object
description: SPAM error correction information.
required:
- mean
properties:
mean:
type: integer
description: Mean SPAM value.
minimum: 0
stderr:
type: integer
description: SPAM error.
minimum: 0
timing:
type: object
description: 'Time, in seconds, of various system properties: `t1` time, `t2` time, `1q` gate time, `2q` gate time, `readout` time, and qubit `reset` time.'
required:
- readout
- reset
properties:
readout:
type: integer
description: Readout time.
reset:
type: integer
description: qubit reset time.
x-codeSamples:
- lang: curl
source: "curl \"https://api.ionq.co/v0.2/characterizations/aa54e783-0a9b-4f73-ad2f-63983b6aa4a8\" \\\n -H \"Authorization: apiKey your-api-key\"\n"
components:
securitySchemes:
API_Key:
in: header
name: Authorization
type: apiKey
description: 'We provide API keys to govern access—we''ll provision your account with one key, and more can be provided upon request.
Every key is fully privileged within the system, and should be kept private.
To authenticate, prefix your API Key with `apiKey ` and place it in the `Authorization` request header.
For example: `Authorization: apiKey your-api-key`
'
x-tagGroups:
- name: Managing Jobs
tags:
- jobs
- name: Building Circuits
tags:
- quantum_programs
- name: Characterization Data
tags:
- calibrations
- characterizations
- name: Backends
tags:
- backends
- name: User Metadata
tags:
- metadata
- name: API Features
tags:
- api-feature-pagination
- api-feature-response-status
- name: Telemetry
tags:
- status
x-provenance:
method: harvested
publisher: IonQ
source: https://api.ionq.co/api-docs
note: split by refine-openapis from the provider's own published document, verified by fetch (openapi/_original/*.fetch.json);
stamped by stamp-openapi-provenance.py (roadmap#793)