# Radio field

> Show every singular configured choice while storing the same finite string contract as Select.

Canonical URL: https://riducms.com/docs/fields/radio/

Use `field.Radio` for a small set of mutually exclusive choices that authors should see without
opening a dropdown. Its stored and generated contract is the same singular string union as
[Select](https://riducms.com/docs/fields/select/); only the admin control differs.

## In the admin {#admin-behavior}

![A Tone radio field in the Ridu admin with Friendly selected from three visible choices.](https://raw.githubusercontent.com/riducms/ridu/main/docs/assets/fields/radio.png)

_Labels remain interface copy; the document stores one configured choice value._

## Smallest working example {#example}

```go title="content/posts.go"
field.Radio(
	"priority",
	field.OneOf("low", "normal", "high"),
	field.Default("normal"),
)
```

For clearer author copy, configure explicit choices:

```go title="content/events.go"
field.Radio(
	"attendance",
	field.Choices(
		field.Choice{Value: "remote", Label: "Join online"},
		field.Choice{Value: "venue", Label: "Attend at the venue"},
	),
	field.Required(),
)
```

Radio supports singular `Default`, `Required`, localization, indexing/uniqueness, conditions, and
common presentation options. It does not accept `Multiple` or `DefaultChoices`; use Select
for multiple values.

Queries and generated types use stored values, never labels. Choice labels may be translated
for the admin without localizing the content value. Add `field.Localized()` only when different
locales may select different business values.

## Common mistakes {#troubleshooting}

- Too many radio choices create a slow form. Switch to Select or a Relationship picker as the set
  grows.
- Renaming a `Choice.Value` is a data migration. Changing `Label` is safe presentation copy.
- `ShowWhen` can improve the form but cannot enforce a cross-field rule or access policy.

See [`field.Radio`](https://riducms.com/reference/field/radio/) and [Select](https://riducms.com/docs/fields/select/) for the full choice
contract.