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# List UnitType items

GET https://{tenant_name}.benchling.com/api/v3/unit-type/items

List UnitType items.

Reference: https://docs.benchling.com/docs/api/benchling-api/unit-type/list

## Authentication

- `Authorization` header (bearer token, required) — Bearer authentication of the form `Bearer <token>`, where token is your auth token.

## Request

### Query parameters

- `createdAt.gt` (string, optional) — Datetime, in RFC 3339 format. Time zone defaults to UTC. Restricts results to those created after the specified time. e.g. > 2017-04-30.
- `createdAt.gte` (string, optional) — Datetime, in RFC 3339 format. Time zone defaults to UTC. Restricts results to those created at or after the specified time. e.g. >= 2017-04-30.
- `createdAt.lt` (string, optional) — Datetime, in RFC 3339 format. Time zone defaults to UTC. Restricts results to those created before the specified time. e.g. \< 2017-04-30.
- `createdAt.lte` (string, optional) — Datetime, in RFC 3339 format. Time zone defaults to UTC. Restricts results to those created at or before the specified time. e.g. \<= 2017-04-30.
- `id.anyOf` (string, optional) — Restricts results to those matching any of the specified IDs. Comma-separated list.
- `modifiedAt.gt` (string, optional) — Datetime, in RFC 3339 format. Time zone defaults to UTC. Restricts results to those modified after the specified time. e.g. > 2017-04-30.
- `modifiedAt.gte` (string, optional) — Datetime, in RFC 3339 format. Time zone defaults to UTC. Restricts results to those modified at or after the specified time. e.g. >= 2017-04-30.
- `modifiedAt.lt` (string, optional) — Datetime, in RFC 3339 format. Time zone defaults to UTC. Restricts results to those modified before the specified time. e.g. \< 2017-04-30.
- `modifiedAt.lte` (string, optional) — Datetime, in RFC 3339 format. Time zone defaults to UTC. Restricts results to those modified at or before the specified time. e.g. \<= 2017-04-30.
- `name.anyOf` (string, optional) — Restricts results to those that match any of the specified names. Case insensitive. Warning - this filter can be non-performant due to case insensitivity. Ensure only one name filter is used at a time. Comma-separated list.
- `name.anyOf.caseSensitive` (string, optional) — Restricts results to those that match any of the specified names. Case sensitive. Ensure only one name filter is used at a time. Comma-separated list.
- `nextToken` (string, optional) — Token for pagination
- `omit` (string, optional) — Comma-separated list of top-level fields to omit from each returned item. Cannot overlap with returning.
- `pageSize` (integer, optional) — Number of results to return. Defaults to 50, maximum of 100.
- `returning` (string, optional) — Comma-separated list of top-level fields to include in each returned item. Cannot overlap with omit.
- `sort` (enum, optional, default: modifiedAt:desc) — Method by which to order results. Valid sorts are: createdAt (created time, oldest first) and modifiedAt (modified time, oldest first). Use :asc or :desc to specify ascending or descending order. Default is modifiedAt:desc.
  - Allowed values: `createdAt:asc`, `createdAt:desc`, `modifiedAt:asc`, `modifiedAt:desc`

## Response

### 200

OK

- `items` (list of UnitType, optional)
- `nextToken` (string, optional)

## Errors

### 400 Unit Type List Request Bad Request Error

Bad Request

- `detail` (GeneralErrorDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `invalidId` (string, optional)

### 403 Unit Type List Request Forbidden Error

Forbidden

- `detail` (GeneralErrorDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `invalidId` (string, optional)

### 404 Unit Type List Request Not Found Error

Not Found

- `detail` (GeneralErrorDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `invalidId` (string, optional)

### 429 Unit Type List Request Too Many Requests Error

Too Many Requests

- `detail` (TooManyRequestsErrorBodyDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `invalidId` (string, optional)
- `violated-policies` (list of enum, optional) — The budget policies that rejected the request, in canonical order: `user`, `integration`, then `tenant`.
  - Allowed values: `user`, `integration`, `tenant`

### 500 Unit Type List Request Internal Server Error

Internal Server Error

- `detail` (InternalServerErrorBodyDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `errorId` (string, optional)

## Types

### UnitType

A UnitType is a dimensional category that groups inter-convertible `Unit` objects within Benchling's tenant-specific unit dictionary. Examples include Volume, Mass, Time, Molar Concentration, and custom types like Cell Concentration. Each UnitType has a designated `baseUnit` that serves as the reference for conversion factors of all other units in the type—units within the same UnitType can be converted to each other, but cross-dimensional conversions are not supported. The dimensional composition is described by `terms` (see `UnitTypeTerm`), and derived types can specify their `formula` (see `FormulaUnitTerm`) to define relationships like Liter = decimeter³. UnitTypes can be flagged to provide concentration units or container quantity units for inventory features regardless of their dimensional terms. Historically called "Quantity" in some internal systems.

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable)
- `archived` (boolean, optional)
- `baseUnit` (UnitRef, optional, nullable) — The reference unit. All other units' conversionFactors are relative to this unit. Null for unit types with no units yet.
- `createdAt` (string, optional, nullable)
- `formula` (list of FormulaUnitTerm, optional, nullable) — Defines this unit type in terms of other units for derived types, e.g. Liter = decimeter cubed.
- `id` (string, optional)
- `modifiedAt` (string, optional, nullable)
- `name` (string, optional) — The user-facing name, e.g. "Volume" or "Molar Concentration".
- `overrideIsConcentration` (boolean, optional, nullable) — When true, forces this UnitType to be treated as a concentration type regardless of its terms. When false, the classification is determined by the UnitType's terms. Mutually exclusive with `overrideIsContainerQuantity`.
- `overrideIsContainerQuantity` (boolean, optional, nullable) — When true, forces this UnitType to be treated as a container quantity type regardless of its terms. When false, the classification is determined by the UnitType's terms. Mutually exclusive with `overrideIsConcentration`.
- `terms` (list of UnitTypeTerm, optional) — The dimensional composition of this unit type as a list of SI base dimensions with exponents.
- `units` (string, optional, nullable) — All units belonging to this unit type.

### GeneralErrorDetail

### TooManyRequestsErrorBodyDetail

### InternalServerErrorBodyDetail

### UnitRef

- `__typename` (string, optional)
- `id` (string, optional)

### FormulaUnitTerm

A term in the original formula of a `UnitType` that references an actual `Unit` rather than a base dimension. This is used to define relationships between units across different UnitTypes, such as defining that Liter = decimeter³. Unlike `UnitTypeTerm` which uses abstract SI dimensions, FormulaUnitTerm references concrete Unit definitions and is the crucial piece for establishing mathematical relationships when composing derived unit types.

- `__typename` (string, optional)
- `exponent` (integer, optional)
- `value` (UnitRef, optional)

### UnitTypeTerm

A term in the dimensional formula of a `UnitType`, pairing one of the seven SI base dimensions (see `BaseUnitType`) with an integer exponent. Multiple terms together describe the dimensional composition of a UnitType. For example, a Volume UnitType would have a single term with value=LENGTH and exponent=3, while Acceleration would have [LENGTH^1, TIME^-2]. Terms are descriptive metadata and do not uniquely identify a UnitType—multiple UnitTypes can share the same dimensional terms.

- `__typename` (string, optional)
- `exponent` (integer, optional)
- `value` (enum, optional)
  - Allowed values: `TIME`, `LENGTH`, `MASS`, `CURRENT`, `TEMPERATURE`, `AMOUNT`, `LUMINOUS_INTENSITY`

## Examples

**Response**

```json
{
  "items": [
    {
      "__typename": "__typename",
      "archiveReason": "archiveReason",
      "archived": true,
      "createdAt": "createdAt",
      "formula": [
        {}
      ],
      "id": "id",
      "modifiedAt": "modifiedAt",
      "name": "name",
      "overrideIsConcentration": true,
      "overrideIsContainerQuantity": true,
      "terms": [
        {}
      ],
      "units": "units"
    }
  ],
  "nextToken": "nextToken"
}
```

**SDK Code**

```python
import requests

url = "https://{tenant_name}.benchling.com/api/v3/unit-type/items"

headers = {"Authorization": "Bearer <token>"}

response = requests.get(url, headers=headers)

print(response.json())
```

```javascript
const url = 'https://{tenant_name}.benchling.com/api/v3/unit-type/items';
const options = {method: 'GET', headers: {Authorization: 'Bearer <token>'}};

try {
  const response = await fetch(url, options);
  const data = await response.json();
  console.log(data);
} catch (error) {
  console.error(error);
}
```