diff --git a/CHANGELOG.md b/CHANGELOG.md
index b749d19..4b9e635 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,12 @@
 > - :house: [Internal]
 > - :nail_care: [Polish]
 
+## Unreleased
+
+#### :rocket: New Feature
+
+- Add `ReactEvent.Toggle` with typed `oldState`, `newState`, and optional `source` accessors and synthetic-event helpers.
+
 ## 0.16.0-beta.1
 
 #### :boom: Breaking Change
diff --git a/src/ReactEvent.res b/src/ReactEvent.res
index 54ac591..6c82589 100644
--- a/src/ReactEvent.res
+++ b/src/ReactEvent.res
@@ -241,3 +241,15 @@ module Transition = {
   @get external pseudoElement: t => string = "pseudoElement"
   @get external elapsedTime: t => float = "elapsedTime"
 }
+
+module Toggle = {
+  type tag = JsxEvent.Toggle.tag
+  type t = synthetic<tag>
+
+  include MakeEventWithType({type t = t})
+
+  @get external oldState: t => [#closed | #"open"] = "oldState"
+  @get external newState: t => [#closed | #"open"] = "newState"
+  /** The element that triggered the toggle. Available in React 19.3 and later. */
+  @get @return(nullable) external source: t => option<Dom.element> = "source"
+}
diff --git a/src/ReactEvent.res.js b/src/ReactEvent.res.js
index 5303ddd..ac17a6e 100644
--- a/src/ReactEvent.res.js
+++ b/src/ReactEvent.res.js
@@ -33,6 +33,8 @@ let Animation = {};
 
 let Transition = {};
 
+let Toggle = {};
+
 export {
   Synthetic,
   Clipboard,
@@ -50,5 +52,6 @@ export {
   Image,
   Animation,
   Transition,
+  Toggle,
 }
 /* No side effect */
diff --git a/src/ReactEvent.resi b/src/ReactEvent.resi
index 61b5d4b..4b04da3 100644
--- a/src/ReactEvent.resi
+++ b/src/ReactEvent.resi
@@ -470,3 +470,27 @@ module Transition: {
   @get external pseudoElement: t => string = "pseudoElement"
   @get external elapsedTime: t => float = "elapsedTime"
 }
+
+module Toggle: {
+  type tag = JsxEvent.Toggle.tag
+  type t = synthetic<tag>
+  @get external bubbles: t => bool = "bubbles"
+  @get external cancelable: t => bool = "cancelable"
+  @get external currentTarget: t => {..} = "currentTarget"
+  @get external defaultPrevented: t => bool = "defaultPrevented"
+  @get external eventPhase: t => int = "eventPhase"
+  @get external isTrusted: t => bool = "isTrusted"
+  @get external nativeEvent: t => {..} = "nativeEvent"
+  @send external preventDefault: t => unit = "preventDefault"
+  @send external isDefaultPrevented: t => bool = "isDefaultPrevented"
+  @send external stopPropagation: t => unit = "stopPropagation"
+  @send external isPropagationStopped: t => bool = "isPropagationStopped"
+  @get external target: t => {..} = "target"
+  @get external timeStamp: t => float = "timeStamp"
+  @get external type_: t => string = "type"
+  @send external persist: t => unit = "persist"
+  @get external oldState: t => [#closed | #"open"] = "oldState"
+  @get external newState: t => [#closed | #"open"] = "newState"
+  /** The element that triggered the toggle. Available in React 19.3 and later. */
+  @get @return(nullable) external source: t => option<Dom.element> = "source"
+}