---
title: ECS fields
description: Meta-information specific to ECS. 
url: https://www.elastic.co/docs/reference/ecs/ecs-ecs
products:
  - Elastic Common Schema (ECS)
applies_to:
  - Elastic Cloud Serverless: Generally available
  - Elastic Stack: Generally available
---

# ECS fields
Meta-information specific to ECS.

## ECS field details


| Field                             | Description                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         | Level |
|-----------------------------------| |-------|
| [ecs.version](#field-ecs-version) | ECS version this event conforms to. `ecs.version` is a required field and must exist in all events.When querying across multiple indices -- which may conform to slightly different ECS versions -- this field lets integrations adjust to the schema version of the events.type: keywordexample: `1.0.0`![OTel Badge](https://img.shields.io/badge/OpenTelemetry-4a5ca6?style=flat&logo=opentelemetry) [![not-applicable](https://img.shields.io/badge/n%2Fa-f2f4fb?style=flat)](/docs/reference/ecs/ecs-opentelemetry#ecs-opentelemetry-relation) Not applicable. | core  |