# Label reference

Labels are user-defined key-value pairs used to organize and categorize your resources. See the [labels explanation](/operate/explanations/labels.md) for background.

## Format

A label consists of a key and a value:

```text
<key>: <value>
```

| Part | Description |
| :--- | :--- |
| `<key>` | Your label name. Must follow the [Kubernetes label syntax](https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/#syntax-and-character-set). |
| `<value>` | Your label value. Must follow the [Kubernetes label syntax](https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/#syntax-and-character-set). |

## Behavior

- Labels are kept **verbatim** — Nais does not rewrite or strip them.
- Labels are **propagated** to the underlying Kubernetes resources that the resource owns.
- Labels carry **no special meaning** to Nais. They are only used for your own organization.

## Hidden labels

[Nais Console](/operate/console.md) and the [Nais API](/operate/console/api.md) surface all labels on a resource, except for the following internal labels, which are hidden:

| Label key | Match |
| :--- | :--- |
| `app` | Exact match |
| `team` | Exact match |
| `*nais.io/*` | Any key containing the substring `nais.io/` |

Hidden labels remain present on the underlying Kubernetes resources.

## Setting labels

Labels are defined under `metadata.labels` for any Kubernetes resource that Nais supports:

```yaml
apiVersion: nais.io/v1alpha1
kind: Application
metadata:
  name: myapplication
  namespace: myteam
  labels:
    team-area: payments
    sensitive: "true"
spec:
  ...
```

Labels can also be added and edited from [Nais Console](/operate/console.md) for [Valkey](/persistence/valkey.md), [OpenSearch](/persistence/opensearch.md), [Config](/services/config.md), and [Secret](/services/secrets.md).

## Related pages

🎯 [Add labels to your resources](/operate/how-to/labels.md)

💡 [Learn more about labels](/operate/explanations/labels.md)