diff --git a/frontend/src/components/Sidebar.tsx b/frontend/src/components/Sidebar.tsx
index 5e43440..8d28ed4 100644
--- a/frontend/src/components/Sidebar.tsx
+++ b/frontend/src/components/Sidebar.tsx
@@ -14,6 +14,7 @@ import {
 } from "lucide-react";
 import type { Conversation, User } from "../lib/types.ts";
 import { api } from "../lib/api.ts";
+import { useT } from "../lib/i18n.ts";
 import { Avatar, Button, ContextMenu, FlowerMark, IconButton } from "./ui.tsx";
 import { cn } from "../lib/cn.ts";
 
@@ -58,6 +59,7 @@ export function Sidebar({
   mobileOpen: boolean;
   onCloseMobile: () => void;
 }) {
+  const { t } = useT();
   const [menu, setMenu] = useState<MenuState | null>(null);
   const [query, setQuery] = useState("");
   const [results, setResults] = useState<(Conversation & { snippet: string | null; snippetRole: string | null })[] | null>(null);
@@ -132,12 +134,12 @@ export function Sidebar({
         <div className="flex items-center gap-1">
           <Button variant="secondary" size="sm" className="flex-1" onClick={onNew}>
             <MessageSquarePlus size={16} />
-            New chat
+            {t("sidebar.newChat")}
           </Button>
-          <IconButton title="Collapse sidebar" onClick={onToggle} className="hidden md:inline-flex">
+          <IconButton title={t("sidebar.collapse")} onClick={onToggle} className="hidden md:inline-flex">
             <PanelLeftClose size={18} />
           </IconButton>
-          <IconButton title="Close chats" onClick={onCloseMobile} className="md:hidden">
+          <IconButton title={t("sidebar.closeDrawer")} onClick={onCloseMobile} className="md:hidden">
             <X size={18} />
           </IconButton>
         </div>
@@ -146,13 +148,13 @@ export function Sidebar({
           <input
             value={query}
             onChange={(e) => setQuery(e.target.value)}
-            placeholder="Search chats…"
-            aria-label="Search conversations"
+            placeholder={t("sidebar.searchPh")}
+            aria-label={t("sidebar.searchAria")}
             className="w-full rounded-2xl border border-stone-200/70 bg-stone-100 py-2 pl-9 pr-8 text-sm outline-none transition placeholder:text-stone-400 focus:border-accent-500/60 focus:bg-white dark:border-zinc-800 dark:bg-zinc-800/60 dark:placeholder:text-zinc-500 dark:focus:bg-zinc-900"
           />
           {query && (
             <button
-              aria-label="Clear search"
+              aria-label={t("sidebar.clearSearch")}
               onClick={() => setQuery("")}
               className="absolute right-2.5 top-1/2 -translate-y-1/2 rounded-full p-0.5 opacity-60 transition hover:opacity-100"
             >
@@ -164,9 +166,9 @@ export function Sidebar({
       <div className="flex-1 space-y-1 overflow-y-auto py-1">
         {results !== null ? (
           <>
-            {searching && <p className="px-3 py-4 text-center text-sm opacity-50">Searching…</p>}
+            {searching && <p className="px-3 py-4 text-center text-sm opacity-50">{t("sidebar.searching")}</p>}
             {!searching && results.length === 0 && (
-              <p className="px-3 py-6 text-center text-sm opacity-50">No match for “{query.trim()}”.</p>
+              <p className="px-3 py-6 text-center text-sm opacity-50">{t("sidebar.noMatch", { q: query.trim() })}</p>
             )}
             {results.map((c) => (
               <div
@@ -185,7 +187,7 @@ export function Sidebar({
                 <span className="block truncate">{c.title}</span>
                 {c.snippet && (
                   <span className="mt-0.5 block truncate text-xs opacity-60">
-                    {c.snippetRole === "user" ? "you: " : ""}{c.snippet}
+                    {c.snippetRole === "user" ? t("sidebar.youPrefix") : ""}{c.snippet}
                   </span>
                 )}
               </div>
diff --git a/frontend/src/components/dialogs.tsx b/frontend/src/components/dialogs.tsx
index 2eec233..0d46689 100644
--- a/frontend/src/components/dialogs.tsx
+++ b/frontend/src/components/dialogs.tsx
@@ -805,25 +805,25 @@ function SecuritySection({ onKeyRotated }: { onKeyRotated?: () => void }) {
   return (
     <div className="space-y-5">
       <div>
-        <p className="mb-1 flex items-center gap-1.5 text-sm font-medium"><KeyRound size={14} className="opacity-60" /> Access key</p>
-        <p className="mb-2 text-xs opacity-60">Rotate your access key. Old sessions are revoked immediately — you'll log back in with the new key.</p>
-        <Button size="sm" variant="secondary" type="button" disabled={busy} onClick={rotate}>
-          {armingRotate ? "Click again to confirm rotation" : "Rotate my access key"}
+        <p className="mb-1 flex items-center gap-1.5 text-sm font-medium"><KeyRound size={14} className="opacity-60" /> {t("sec.accessKey")}</p>
+        <p className="mb-2 text-xs opacity-60">{t("sec.accessKeyHint")}</p>
+        <Button size="sm" variant="secondary" disabled={busy} onClick={rotate}>
+          {armingRotate ? t("sec.rotateConfirm") : t("sec.rotate")}
         </Button>
       </div>
 
       <div>
-        <p className="mb-1 flex items-center gap-1.5 text-sm font-medium"><ShieldCheck size={14} className="opacity-60" /> Two-factor (TOTP)</p>
-        {totpOn === null && <p className="flex items-center gap-2 text-sm opacity-60"><Spinner size={14} /> Checking…</p>}
+        <p className="mb-1 flex items-center gap-1.5 text-sm font-medium"><ShieldCheck size={14} className="opacity-60" /> {t("sec.totp")}</p>
+        {totpOn === null && <p className="flex items-center gap-2 text-sm opacity-60"><Spinner size={14} /> {t("sec.totpChecking")}</p>}
         {totpOn === false && !secret && (
           <>
-            <p className="mb-2 text-xs opacity-60">Add a 6-digit code from your authenticator app on top of your access key.</p>
-            <Button size="sm" variant="secondary" type="button" disabled={busy} onClick={startTotp}>Enable two-factor</Button>
+            <p className="mb-2 text-xs opacity-60">{t("sec.totpAddHint")}</p>
+            <Button size="sm" variant="secondary" disabled={busy} onClick={startTotp}>{t("sec.totpEnable")}</Button>
           </>
         )}
         {secret && (
           <div className="space-y-2 rounded-2xl border border-stone-200 p-3 dark:border-zinc-700">
-            <p className="text-xs opacity-70">Add this secret to your authenticator app (or open the otpauth link), then enter a code to confirm:</p>
+            <p className="text-xs opacity-70">{t("sec.totpSecretHint")}</p>
             <div className="flex items-center gap-2">
               <code className="min-w-0 flex-1 break-all rounded-xl bg-stone-100 px-3 py-2 font-mono text-sm dark:bg-zinc-800">{secret}</code>
               <CopyButton text={secret} />
@@ -834,30 +834,30 @@ function SecuritySection({ onKeyRotated }: { onKeyRotated?: () => void }) {
                 value={code}
                 onChange={(e) => setCode(e.target.value.replace(/\D/g, "").slice(0, 6))}
                 placeholder="000000"
-                aria-label="Authenticator code"
+                aria-label={t("login.totpAria")}
                 inputMode="numeric"
                 className="text-center tracking-[0.4em]"
               />
-              <Button size="sm" type="button" disabled={busy || code.length !== 6} onClick={confirmTotp}>Confirm</Button>
+              <Button size="sm" disabled={busy || code.length !== 6} onClick={confirmTotp}>{t("sec.totpConfirm")}</Button>
             </div>
           </div>
         )}
         {totpOn === true && (
           <div className="flex flex-wrap items-end gap-2">
             <div className="min-w-36 flex-1">
-              <Field label="Disable with a current code">
+              <Field label={t("sec.totpDisableLabel")}>
                 <Input
                   value={code}
                   onChange={(e) => setCode(e.target.value.replace(/\D/g, "").slice(0, 6))}
                   placeholder="000000"
-                  aria-label="Current authenticator code"
+                  aria-label={t("login.totpAria")}
                   inputMode="numeric"
                   className="text-center tracking-[0.4em]"
                 />
               </Field>
             </div>
-            <Button size="sm" variant="secondary" type="button" disabled={busy || code.length !== 6} onClick={disableTotp} className="!text-red-600 dark:!text-red-400">
-              Disable 2FA
+            <Button size="sm" variant="secondary" disabled={busy || code.length !== 6} onClick={disableTotp} className="!text-red-600 dark:!text-red-400">
+              {t("sec.totpDisable")}
             </Button>
           </div>
         )}
@@ -866,31 +866,31 @@ function SecuritySection({ onKeyRotated }: { onKeyRotated?: () => void }) {
       <div className="flex items-center gap-3 rounded-2xl px-1 py-1 opacity-50">
         <Fingerprint size={16} />
         <span className="min-w-0 flex-1">
-          <span className="block text-sm font-medium">Passkeys <span className="ml-1 text-xs opacity-60">(soon)</span></span>
-          <span className="block text-xs opacity-60">WebAuthn / platform authenticators — needs a server RP setup.</span>
+          <span className="block text-sm font-medium">{t("sec.passkeys")} <span className="ml-1 text-xs opacity-60">{t("feat.soon")}</span></span>
+          <span className="block text-xs opacity-60">{t("sec.passkeysHint")}</span>
         </span>
       </div>
 
       <div className="rounded-2xl border border-red-500/30 p-3">
         <p className="mb-1 flex items-center gap-1.5 text-sm font-medium text-red-600 dark:text-red-400">
-          <Trash2 size={14} /> Danger zone
+          <Trash2 size={14} /> {t("sec.danger")}
         </p>
-        <p className="mb-2 text-xs opacity-60">Permanently delete your account with all chats, shares and sessions. Cannot be undone.</p>
-        <Button size="sm" variant="secondary" type="button" disabled={busy} onClick={() => setConfirmDelete(true)} className="!text-red-600 dark:!text-red-400">
-          Delete my account
+        <p className="mb-2 text-xs opacity-60">{t("sec.dangerHint")}</p>
+        <Button size="sm" variant="secondary" disabled={busy} onClick={() => setConfirmDelete(true)} className="!text-red-600 dark:!text-red-400">
+          {t("sec.deleteMe")}
         </Button>
       </div>
 
       {error && <p className="text-sm text-red-600 dark:text-red-400">{error}</p>}
 
-      <Modal open={rotatedKey !== null} onClose={() => {}} title="New access key" icon={KeyRound}>
+      <Modal open={rotatedKey !== null} onClose={() => {}} title={t("sec.newKeyTitle")} icon={KeyRound}>
         <div className="space-y-4">
-          <p className="text-sm opacity-80">Copy it now — it won't be shown again. Your old sessions are revoked.</p>
+          <p className="text-sm opacity-80">{t("sec.newKeyHint")}</p>
           <div className="flex items-center gap-2">
             <code className="min-w-0 flex-1 truncate rounded-2xl bg-stone-100 px-3 py-2.5 font-mono text-sm dark:bg-zinc-800">{rotatedKey}</code>
             {rotatedKey && <CopyButton text={rotatedKey} />}
           </div>
-          <Button size="sm" className="w-full" onClick={() => onKeyRotated?.()}>Done — log me out</Button>
+          <Button size="sm" className="w-full" onClick={() => onKeyRotated?.()}>{t("sec.newKeyDone")}</Button>
         </div>
       </Modal>
 
@@ -898,9 +898,9 @@ function SecuritySection({ onKeyRotated }: { onKeyRotated?: () => void }) {
         open={confirmDelete}
         onClose={() => setConfirmDelete(false)}
         onConfirm={removeAccount}
-        title="Delete your account?"
-        message="This permanently removes your account with all conversations, shares and sessions. This cannot be undone."
-        confirmLabel="Delete forever"
+        title={t("sec.deleteTitle")}
+        message={t("sec.deleteMsg")}
+        confirmLabel={t("sec.deleteForever")}
       />
     </div>
   );