diff --git a/src/uix/active-uix/id/index.ts b/src/uix/active-uix/id/index.ts
new file mode 100644
index 000000000..4c8e40f3b
--- /dev/null
+++ b/src/uix/active-uix/id/index.ts
@@ -0,0 +1,24 @@
+/**
+ * Process-unique client-side id counter.
+ *
+ * `useId()` returns the next value of a monotonic module-level counter —
+ * cheaper than `Date.now()` and, unlike a timestamp, collision-free. Use it
+ * for client-only ephemeral ids (list keys, generated handles).
+ *
+ * NOT for SSR / ARIA element ids derived from the component tree — those use
+ * soma's `createId`, which wraps Svelte's `$props.id()` for hydration-stable
+ * output. A global counter would desync between server and client renders.
+ *
+ * Lives in active-uix (not soma) so any UIX layer — soma, eidos, demos,
+ * apps — can mint ids without coupling to soma. Imported by subpath
+ * (`$active-uix/id`), mirroring `$active-uix/prefs`, so it never pulls the
+ * runtime barrel. The `soma-` prefix is the shared UIX id convention (same
+ * shape `createId` emits), not a marker of where this lives.
+ */
+
+let counter = 0
+
+export function useId(component = ''): string {
+	const id = ++counter
+	return component ? `soma-${component}-${id}` : `soma-${id}`
+}
diff --git a/src/uix/soma/SOMA_ARCHITECTURE.md b/src/uix/soma/SOMA_ARCHITECTURE.md
index 0b39ea915..74bdc1ff8 100644
--- a/src/uix/soma/SOMA_ARCHITECTURE.md
+++ b/src/uix/soma/SOMA_ARCHITECTURE.md
@@ -838,7 +838,7 @@ src/uix/soma/
 ├── keyboard/                  ← KEYS, directional
 ├── dom/                       ← DOM utilities, focus
 ├── css/                       ← styleToString, cssToStyleObj
-├── id/                        ← createId, useId
+├── id/                        ← createId  (useId → $active-uix/id)
 ├── types/                     ← shared types + service interfaces
 ├── layers/                    ← behavior layers (classes only)
 │   ├── presence.svelte.ts
diff --git a/src/uix/soma/components/accordion/components/accordion-item.svelte b/src/uix/soma/components/accordion/components/accordion-item.svelte
index ccc245efd..99e6068f4 100644
--- a/src/uix/soma/components/accordion/components/accordion-item.svelte
+++ b/src/uix/soma/components/accordion/components/accordion-item.svelte
@@ -4,7 +4,8 @@
 	writableActive
 } from '$libs/reactive';
 	import { mergeProps } from '../../../props';
-	import { createId, useId } from '../../../id';
+	import { createId } from '../../../id';
+	import { useId } from '$active-uix/id';
 	import { AccordionItemProvider } from '../accordion-provider.svelte';
 	import type { AccordionItemProps } from '../types';
 
diff --git a/src/uix/soma/components/date-field/date-field-provider.svelte.ts b/src/uix/soma/components/date-field/date-field-provider.svelte.ts
index 5422a5455..c6672c7f3 100644
--- a/src/uix/soma/components/date-field/date-field-provider.svelte.ts
+++ b/src/uix/soma/components/date-field/date-field-provider.svelte.ts
@@ -21,7 +21,7 @@ import type {
 } from '../../types';
 import { KEYS, getDirectionalKeys } from '../../keyboard';
 import { isNumberString } from '../../types/guards';
-import { useId } from '../../id';
+import { useId } from '$active-uix/id';
 import { Soma } from '../../core/soma.svelte';
 import {
 	DateFormatter,
diff --git a/src/uix/soma/components/internal/arrow.svelte b/src/uix/soma/components/internal/arrow.svelte
index 41c6d91ca..23ab414c7 100644
--- a/src/uix/soma/components/internal/arrow.svelte
+++ b/src/uix/soma/components/internal/arrow.svelte
@@ -1,6 +1,6 @@
 <script lang="ts">
 	import { mergeProps } from '../../props';
-	import { useId } from '../../id';
+	import { useId } from '$active-uix/id';
 	import type { WithChild, PrimitiveSpanAttributes } from '../../types';
 
 	type ArrowProps = WithChild<{
diff --git a/src/uix/soma/components/time-field/time-field-provider.svelte.ts b/src/uix/soma/components/time-field/time-field-provider.svelte.ts
index 54990df45..829846716 100644
--- a/src/uix/soma/components/time-field/time-field-provider.svelte.ts
+++ b/src/uix/soma/components/time-field/time-field-provider.svelte.ts
@@ -12,7 +12,7 @@ import {
 import type { SomaFocusEvent, SomaKeyboardEvent, OnChangeFn } from '../../types';
 import { KEYS, getDirectionalKeys } from '../../keyboard';
 import { isNumberString } from '../../types/guards';
-import { useId } from '../../id';
+import { useId } from '$active-uix/id';
 import { Soma } from '../../core/soma.svelte';
 import {
 	DateFormatter,
diff --git a/src/uix/soma/components/toast/toaster.svelte.ts b/src/uix/soma/components/toast/toaster.svelte.ts
index d9f89d90f..8b566efe0 100644
--- a/src/uix/soma/components/toast/toaster.svelte.ts
+++ b/src/uix/soma/components/toast/toaster.svelte.ts
@@ -1,4 +1,4 @@
-import { useId } from '../../id';
+import { useId } from '$active-uix/id';
 import type { Intent } from '$uix/intent';
 
 // ── Types ────────────────────────────────────────────────────────────────────
diff --git a/src/uix/soma/id/create-id.ts b/src/uix/soma/id/create-id.ts
index ded74ac79..86e291c3c 100644
--- a/src/uix/soma/id/create-id.ts
+++ b/src/uix/soma/id/create-id.ts
@@ -1,5 +1,3 @@
-let counter = 0;
-
 /**
  * Create an ID from a Svelte $props.id() uid, with optional component context.
  *
@@ -7,13 +5,11 @@ let counter = 0;
  * createId(uid)                    // "soma-c12"
  * createId(uid, 'dialog-trigger')  // "soma-dialog-trigger-c12"
  * ```
+ *
+ * This is soma's ARIA/DOM id helper: the `uid` comes from the component's
+ * `$props.id()`, so the output is hydration-stable (deterministic per render
+ * tree). For a generic client-only counter, use `useId` from `$active-uix/id`.
  */
 export function createId(uid: string, component?: string): string {
 	return component ? `soma-${component}-${uid}` : `soma-${uid}`;
 }
-
-/** Generate a unique ID with component context. */
-export function useId(component = ''): string {
-	const id = ++counter;
-	return component ? `soma-${component}-${id}` : `soma-${id}`;
-}
diff --git a/src/uix/soma/id/index.ts b/src/uix/soma/id/index.ts
index c96011c39..7169821a9 100644
--- a/src/uix/soma/id/index.ts
+++ b/src/uix/soma/id/index.ts
@@ -1 +1 @@
-export { createId, useId } from './create-id';
+export { createId } from './create-id';
diff --git a/src/uix/soma/layers/floating/floating.svelte.ts b/src/uix/soma/layers/floating/floating.svelte.ts
index 2f1d88ef8..0a5f54b11 100644
--- a/src/uix/soma/layers/floating/floating.svelte.ts
+++ b/src/uix/soma/layers/floating/floating.svelte.ts
@@ -15,7 +15,7 @@ import { cssToStyleObj, styleToString } from '../../css';
 import type { ActiveDom } from '$adom';
 import { state, readableActive, type Active, type ActiveProps } from '$libs/reactive';
 import { isNotNull } from '../../types';
-import { useId } from '../../id';
+import { useId } from '$active-uix/id';
 import { context, type SomaContext } from '../../provider';
 import type { Arrayable, Direction, StyleProperties } from '../../types';
 import type { WithRefOpts } from '../../provider';