> ## Documentation Index
> Fetch the complete documentation index at: https://docs.markifact.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Create Lookalike Audience

> Create a Meta lookalike audience from an existing source custom audience

Create a Meta lookalike audience from an existing source custom audience. Use meta\_list\_custom\_audiences first to find origin\_audience\_id. The origin audience must have at least 100 people.

| | |
| - | - |
| **App** | Meta Ads |
| **Operation ID** | `meta_create_lookalike_audience` |
| **Type** | Action |
| **Connection** | `meta_ads` (required) |
| **Credits per run** | 1 |
| **Agent / MCP tool** | Yes |
| **Requires approval** | Yes (write operation) |

## Inputs

| Field | Type | Required | Default | Description |
| - | - | - | - | - |
| `account` | DynamicAccount | Yes | - | Select Meta Ads account, ask the user for it if not provided. |
| `name` | string | Yes | - | Name for the lookalike audience. |
| `description` | string | No | - | Optional audience description. |
| `origin_audience_id` | string or SelectItem | Yes | - | Source custom audience ID used as the seed. Use meta\_list\_custom\_audiences to find it. Meta requires the origin audience to have at least 100 people. |
| `country` | string or SelectItem | No | - | Two-letter country code for the simple lookalike spec, e.g. US, AE, GB. Required unless lookalike\_spec is provided. |
| `ratio` | number | No | `0.01` | Simple lookalike size as a decimal from 0.01 to 0.20 in 0.01 increments. 0.01 means the top 1% most similar audience in the selected country. |
| `starting_ratio` | number | No | - | Optional start percentage for a lookalike range. Example: starting\_ratio=0.01 and ratio=0.02 creates a 1%-2% lookalike. Must be less than ratio. |
| `allow_international_seeds` | boolean | No | - | Optional Meta flag for simple specs. If true, Meta can use seed members from another country when the selected country has fewer than 100 seed members. |
| `lookalike_spec` | object or string | No | - | Advanced Meta lookalike\_spec object as a dict/object or string. Use this only when simple country/ratio fields are not enough. Must include either country or location\_spec, and either ratio or type. Examples: \{'country': 'US', 'ratio': 0.01}; \{'country': 'US', 'starting\_ratio': 0.01, 'ratio': 0.02}; \{'location\_spec': \{'geo\_locations': \{'countries': \['US', 'CA']}}, 'ratio': 0.01}; \{'country': 'US', 'type': 'similarity'}. Do not include origin\_audience\_id, account\_id, name, or subtype. |

### SelectItem

| Field | Type | Required | Default | Description |
| - | - | - | - | - |
| `value` | string | Yes | - | The value of the selectable item. |
| `label` | string | Yes | - | The label of the selectable item, used for display purposes. If not provided, defaults to the value. |

## Output

**Type**: `Dict`

Returns created lookalike audience id and name.

**Fields**: `audience_id`, `name`


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