---
title: "Get the current CO2 MOER index"
method: GET
path: "/v3/signal-index"
tags: ["GET Index"]
---

# Get the current CO2 MOER index

`GET /v3/signal-index`

Returns the current index value for the specified `region` for the `co2_moer` signal type. This 0-100 value is the statistical percentile of the current MOER relative to the upcoming 24 hours of forecast MOER values for the specified location (100=dirtiest, 0=cleanest). Values are updated periodically (e.g. at 5-minute frequency), and each value is valid starting from its `point_time` for the duration described in `data_point_period_seconds`. No historical query is available for this endpoint.

Data from this endpoint is available for free to all users in all covered regions.

## Query parameters

- `region` string, required — Region abbreviation associated with location, from result of query to `/v3/region-from-loc`
- `signal_type` 'co2_moer', required — Only `co2_moer` indices are currently available.

## Response `200`

Successful Response

- V3SignalIndexForecastResponse
  - `data` BaseAPIV3ResponseFormat[], required
    - `point_time` string, date-time, required
    - `value` number, required
  - `meta` V3SignalIndexMetadata, required
    - `data_point_period_seconds` integer, required
    - `region` string, required
    - `signal_type` 'co2_moer', required
    - `units` string, required
    - `warnings` WarningType[], required
      - `type` string, required
      - `message` string, required
    - `model` V3ModelMetadata
      - `date` string, date, required
      - `type` 'interchange' | 'average' | 'binned_regression' | 'heatrate' | 'proxy' | 'synthetic_proxy' | 'forecast'

## Other responses

- `400` — Bad Request
- `403` — Forbidden
- `422` — Unprocessable Entity

---

[API](https://skmtc.dev/watttime/apis/watttime-data-api.md) · [All operations](https://skmtc.dev/watttime/apis/watttime-data-api/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/watttime/watttime-data-api/revisions/2c85341b2839/schema)