diff --git a/web/src/components/MemoReactionListView/ReactionView.tsx b/web/src/components/MemoReactionListView/ReactionView.tsx
index a8803f0be..5297a21c0 100644
--- a/web/src/components/MemoReactionListView/ReactionView.tsx
+++ b/web/src/components/MemoReactionListView/ReactionView.tsx
@@ -4,6 +4,7 @@ import { cn } from "@/lib/utils";
 import { State } from "@/types/proto/api/v1/common_pb";
 import type { Memo } from "@/types/proto/api/v1/memo_service_pb";
 import type { User } from "@/types/proto/api/v1/user_service_pb";
+import { useTranslate } from "@/utils/i18n";
 import { formatReactionTooltip, useReactionActions } from "./hooks";
 
 interface Props {
@@ -14,6 +15,7 @@ interface Props {
 
 const ReactionView = (props: Props) => {
   const { memo, reactionType, users } = props;
+  const t = useTranslate();
   const currentUser = useCurrentUser();
   const hasReaction = users.some((user) => currentUser && user.username === currentUser.username);
   const readonly = memo.state === State.ARCHIVED;
@@ -48,7 +50,7 @@ const ReactionView = (props: Props) => {
           </button>
         </TooltipTrigger>
         <TooltipContent>
-          <p>{formatReactionTooltip(users, reactionType)}</p>
+          <p>{formatReactionTooltip(users, reactionType, t)}</p>
         </TooltipContent>
       </Tooltip>
     </TooltipProvider>
diff --git a/web/src/components/MemoReactionListView/hooks.ts b/web/src/components/MemoReactionListView/hooks.ts
index 6e83b8b33..47b5592b6 100644
--- a/web/src/components/MemoReactionListView/hooks.ts
+++ b/web/src/components/MemoReactionListView/hooks.ts
@@ -6,8 +6,10 @@ import { memoKeys } from "@/hooks/useMemoQueries";
 import { useUsersByNames } from "@/hooks/useUserQueries";
 import type { Memo, Reaction } from "@/types/proto/api/v1/memo_service_pb";
 import type { User } from "@/types/proto/api/v1/user_service_pb";
+import { useTranslate } from "@/utils/i18n";
 
 export type ReactionGroup = Map<string, User[]>;
+export type TranslateFunction = ReturnType<typeof useTranslate>;
 
 export const useReactionGroups = (reactions: Reaction[]): ReactionGroup => {
   const creatorNames = useMemo(() => reactions.map((r) => r.creator), [reactions]);
@@ -70,11 +72,18 @@ export const useReactionActions = ({ memo, onComplete }: UseReactionActionsOptio
   return { hasReacted, handleReactionClick };
 };
 
-export const formatReactionTooltip = (users: User[], reactionType: string): string => {
+export const formatReactionTooltip = (users: User[], reactionType: string, t: TranslateFunction): string => {
   if (users.length === 0) return "";
   const formatUserName = (user: User) => user.displayName || user.username;
+  const separator = t("common.list-separator");
   if (users.length < 5) {
-    return `${users.map(formatUserName).join(", ")} reacted with ${reactionType.toLowerCase()}`;
+    const userList = users.map(formatUserName).join(separator);
+    return t("reaction.reacted-with", { userList: userList, reactionType: reactionType.toLowerCase() });
   }
-  return `${users.slice(0, 4).map(formatUserName).join(", ")} and ${users.length - 4} more reacted with ${reactionType.toLowerCase()}`;
+  const userList = users.slice(0, 4).map(formatUserName).join(separator);
+  return t("reaction.more-reacted-with", {
+    userList: userList,
+    count: users.length - 4,
+    reactionType: reactionType.toLowerCase(),
+  });
 };
diff --git a/web/src/locales/en.json b/web/src/locales/en.json
index 51fbffb55..7ca6e3cd0 100644
--- a/web/src/locales/en.json
+++ b/web/src/locales/en.json
@@ -53,6 +53,7 @@
     "inbox": "Inbox",
     "input": "Input",
     "language": "Language",
+    "list-separator": ", ",
     "last-updated-at": "Last updated at",
     "layout": "Layout",
     "learn-more": "Learn more",
@@ -209,6 +210,10 @@
     "no-memos-found": "No memos found",
     "search-placeholder": "Search content"
   },
+  "reaction": {
+    "reacted-with": "{{userList}} reacted with {{reactionType}}",
+    "more-reacted-with": "{{userList}} and {{count}} more reacted with {{reactionType}}"
+  },
   "resource": {
     "clear": "Clear",
     "copy-link": "Copy Link",