# Portfolios

A **portfolio** is a collection of [projects](https://www.wren.co/docs/api/project-orders) with specific weights that add up to 1. Each project has a different `cost_per_ton`; when combined into a portfolio, we roll up their prices and weights into a single `cost_per_ton` for the portfolio.

When you place an [Offset Order](https://www.wren.co/docs/api/offset-orders), you choose which projects to support by selecting a portfolio. We offer:

1. **Single-project portfolios** — 100% of funds go to one project
2. **Wren Climate Fund** — A curated mix of projects, weighted by funding needs (default)

## GET /api/portfolios

Returns all available portfolios and their project allocations.

GET`/api/portfolios`Copy Path

### Authentication

Optional. Without auth, returns preset portfolios only. With a team or personal API token, may include the user's custom portfolio if it exists. Test tokens behave the same as live tokens here — portfolios are public reference data.

### Query parameters

| Attribute | Type | Description & Constraints |
| --- | --- | --- |
| `expanded` | query | Optional. If present, returns full CamelCase portfolio objects. Without it, returns public API format (snake_case, `image_url`). |

### Success response

HTTP `200`

- `cost_per_ton` — Portfolio-level cost in USD per ton
- `projects[].percentage` — Allocation fraction (e.g. 0.2 = 20%)

### Error responses

None expected for valid requests.