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# Batch create UnitType

POST https://{tenant_name}.benchling.com/api/v3/unit-type:batch-create
Content-Type: application/json

Batch create UnitType synchronously in one transaction. Maximum 25 items per request.

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

## Authentication

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

## Request

### Body (application/json)

This endpoint expects an object.

- `items` (list of CreateUnitTypeInput, required)

## Response

### 201

Created

- `items` (list of UnitType, required)

## Errors

### 400 Unit Type Batch Create 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 Batch Create 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 Batch Create 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)

### 409 Unit Type Batch Create Request Conflict Error

Conflict

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

### 429 Unit Type Batch Create 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 Batch Create 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

### CreateUnitTypeInput

- `baseUnit` (CreateBaseUnitInput, required) — The reference unit for this type.
- `name` (string, required) — The name of this unit type, e.g. "Volume".
- `overrideIsConcentration` (boolean, required) — 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, required) — 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.
- `formula` (list of CreateFormulaUnitTermInput, optional) — Formula defining this type in terms of other units.

### 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

### CreateBaseUnitInput

- `aliases` (list of string, required) — Alternative abbreviations for this unit, i.e. alternate symbols.
- `name` (string, required) — The long-form name, e.g. "milliliter".
- `symbol` (string, required) — The short-form label, e.g. "mL".

### CreateFormulaUnitTermInput

- `exponent` (integer, required) — The exponent applied to the unit.
- `value` (string, required) — The API ID of the unit in this formula term.

### 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

**Request**

```json
{
  "items": [
    {
      "baseUnit": {
        "aliases": [
          "aliases"
        ],
        "name": "name",
        "symbol": "symbol"
      },
      "name": "name",
      "overrideIsConcentration": true,
      "overrideIsContainerQuantity": true
    }
  ]
}
```

**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"
    }
  ]
}
```

**SDK Code**

```python
import requests

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

payload = { "items": [
        {
            "baseUnit": {
                "aliases": ["aliases"],
                "name": "name",
                "symbol": "symbol"
            },
            "name": "name",
            "overrideIsConcentration": True,
            "overrideIsContainerQuantity": True
        }
    ] }
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.json())
```

```javascript
const url = 'https://{tenant_name}.benchling.com/api/v3/unit-type:batch-create';
const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: '{"items":[{"baseUnit":{"aliases":["aliases"],"name":"name","symbol":"symbol"},"name":"name","overrideIsConcentration":true,"overrideIsContainerQuantity":true}]}'
};

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