diff --git a/web/components/StockChart.tsx b/web/components/StockChart.tsx
index bb43c6a..155e633 100644
--- a/web/components/StockChart.tsx
+++ b/web/components/StockChart.tsx
@@ -9,6 +9,7 @@ import {
   type ISeriesApi,
   type LineData,
   type LogicalRange,
+  type MouseEventParams,
   type UTCTimestamp,
 } from "lightweight-charts";
 import type { ChartPayload, LatestPredictionResponse } from "../lib/api";
@@ -42,6 +43,46 @@ function isoToUtcTs(s: string): UTCTimestamp {
 // 한국 거래소 관행: 상승=빨강, 하락=파랑.
 const COLOR_UP = "#ef4444";
 const COLOR_DOWN = "#3b82f6";
+
+// crosshair overlay 용 — 토스 차트는 마우스 hover 시 좌상단에 한국어 정보 박스를 띄움.
+// UTCTimestamp(초) → 'YYYY-MM-DD(요일)' / intraday 면 시:분 까지.
+const WEEKDAYS = ["일", "월", "화", "수", "목", "금", "토"];
+function tsToKLabel(ts: UTCTimestamp, intraday: boolean): string {
+  const d = new Date((ts as number) * 1000);
+  const y = d.getUTCFullYear();
+  const m = String(d.getUTCMonth() + 1).padStart(2, "0");
+  const day = String(d.getUTCDate()).padStart(2, "0");
+  const wd = WEEKDAYS[d.getUTCDay()];
+  const base = `${y}-${m}-${day}(${wd})`;
+  if (!intraday) return base;
+  const hh = String(d.getUTCHours()).padStart(2, "0");
+  const mm = String(d.getUTCMinutes()).padStart(2, "0");
+  return `${base} ${hh}:${mm}`;
+}
+
+// 거래량 한국식 단위 (억/만). 토스 사이드바 fmtCompact 와 동일.
+function fmtKVolume(n: number | null | undefined): string {
+  if (n == null || !Number.isFinite(n)) return "-";
+  if (n >= 1e8) return `${(n / 1e8).toFixed(1)}억`;
+  if (n >= 1e4) return `${(n / 1e4).toFixed(1)}만`;
+  return n.toLocaleString();
+}
+
+function fmtKPrice(n: number | null | undefined): string {
+  if (n == null || !Number.isFinite(n)) return "-";
+  return n.toLocaleString(undefined, { maximumFractionDigits: 0 });
+}
+
+type CrosshairInfo = {
+  label: string;       // '2025-11-28(금)' 또는 '2025-11-28(금) 14:30'
+  open: number | null;
+  high: number | null;
+  low: number | null;
+  close: number | null;
+  volume: number | null;
+  // 시가 → 종가 등락률 (%). null 이면 안 그림.
+  pct: number | null;
+};
 // 예측 캔들은 같은 up/down 색 옅은 톤. "어우러지되 미래 데이터임이 명확" 한 시각 신호.
 const PRED_UP = "#fda4af";
 const PRED_DOWN = "#93c5fd";
@@ -179,6 +220,8 @@ export function StockChart({ chart, prediction }: Props) {
   const [active, setActive] = useState<Set<SmaWindow>>(() => new Set<SmaWindow>([20]));
   const [rsiOn, setRsiOn] = useState(false);
   const [macdOn, setMacdOn] = useState(false);
+  // crosshair 위에 떠 있는 한국어 라벨 — null 이면 hover 안 함 (기본 마지막 봉 표시).
+  const [hover, setHover] = useState<CrosshairInfo | null>(null);
 
   const isIntraday = chart.interval === "10m";
   const showSma = !isIntraday; // 10분봉에선 의미 적음 — UI 도 숨김.
@@ -536,6 +579,69 @@ export function StockChart({ chart, prediction }: Props) {
     sSeries.setData(sLine);
   }, [closes, chart, showMacd]);
 
+  // crosshair → 한국어 오버레이.
+  //  - 같은 time(UTCTimestamp) 의 ohlcv 포인트를 O(1) 조회용 Map 으로 미리 만든다.
+  //  - hover 안 했을 때는 마지막 봉을 기본으로 표시 (토스 패턴 — 차트에 들어오자마자 정보 보임).
+  const ohlcvByTs = useMemo(() => {
+    const m = new Map<number, ChartPayload["ohlcv"][number]>();
+    for (const p of chart.ohlcv) m.set(isoToUtcTs(p.date) as number, p);
+    return m;
+  }, [chart]);
+
+  const lastSummary = useMemo<CrosshairInfo | null>(() => {
+    const pts = chart.ohlcv.filter((p) => p.close != null);
+    if (!pts.length) return null;
+    const last = pts[pts.length - 1];
+    const pct =
+      last.open != null && last.close != null && last.open > 0
+        ? ((last.close - last.open) / last.open) * 100
+        : null;
+    return {
+      label: tsToKLabel(isoToUtcTs(last.date), isIntraday),
+      open: last.open,
+      high: last.high,
+      low: last.low,
+      close: last.close,
+      volume: last.volume,
+      pct,
+    };
+  }, [chart, isIntraday]);
+
+  useEffect(() => {
+    const c = chartRef.current;
+    if (!c) return;
+    const handler = (param: MouseEventParams) => {
+      // 차트 영역 밖이면 hover 해제 → lastSummary 가 자동 표시됨.
+      if (!param.time || !param.point) {
+        setHover(null);
+        return;
+      }
+      const t = param.time as UTCTimestamp;
+      const p = ohlcvByTs.get(t as number);
+      if (!p) {
+        setHover(null);
+        return;
+      }
+      const pct =
+        p.open != null && p.close != null && p.open > 0
+          ? ((p.close - p.open) / p.open) * 100
+          : null;
+      setHover({
+        label: tsToKLabel(t, isIntraday),
+        open: p.open,
+        high: p.high,
+        low: p.low,
+        close: p.close,
+        volume: p.volume,
+        pct,
+      });
+    };
+    c.subscribeCrosshairMove(handler);
+    return () => {
+      c.unsubscribeCrosshairMove(handler);
+    };
+  }, [ohlcvByTs, isIntraday]);
+
   // 메인 ↔ 보조패널 timeScale 단방향 동기화. RSI/MACD 둘 다 처리.
   useEffect(() => {
     const main = chartRef.current;
@@ -630,8 +736,9 @@ export function StockChart({ chart, prediction }: Props) {
           </button>
         </div>
       )}
-      <div className="h-[460px] w-full">
+      <div className="relative h-[460px] w-full">
         <div ref={containerRef} className="h-full w-full" />
+        <CrosshairLabel info={hover ?? lastSummary} isHover={hover != null} />
       </div>
       {showRsi && (
         <div className="mt-2 h-[110px] w-full border-t border-zinc-800 pt-1">
@@ -653,3 +760,71 @@ export function StockChart({ chart, prediction }: Props) {
     </div>
   );
 }
+
+// Toss 차트의 hover 정보 박스. 좌상단 absolute 로 띄우고 pointer-events-none
+// 으로 마우스 이벤트는 그대로 차트가 받음. info=null 이면 표시 안 함.
+function CrosshairLabel({
+  info,
+  isHover,
+}: {
+  info: CrosshairInfo | null;
+  isHover: boolean;
+}) {
+  if (!info) return null;
+  const { label, open, high, low, close, volume, pct } = info;
+  // 등락률 색 — 한국 관행. 0 또는 null 은 회색.
+  const pctCls =
+    pct == null || pct === 0
+      ? "text-zinc-400"
+      : pct > 0
+        ? "text-rose-300"
+        : "text-sky-300";
+  const pctText =
+    pct == null ? "" : `${pct >= 0 ? "+" : ""}${pct.toFixed(2)}%`;
+  return (
+    <div
+      className={`pointer-events-none absolute left-2 top-2 z-10 rounded-md border border-zinc-700/70 bg-zinc-950/80 px-2.5 py-1.5 text-[11px] tabular-nums shadow backdrop-blur-sm ${
+        isHover ? "opacity-100" : "opacity-80"
+      }`}
+    >
+      <div className="mb-0.5 flex items-center gap-1.5 text-zinc-400">
+        <span>{label}</span>
+        {pctText && <span className={pctCls}>{pctText}</span>}
+      </div>
+      <div className="flex flex-wrap gap-x-2 gap-y-0.5 text-zinc-200">
+        <CrosshairCell k="시" v={fmtKPrice(open)} />
+        <CrosshairCell k="고" v={fmtKPrice(high)} tone="up" />
+        <CrosshairCell k="저" v={fmtKPrice(low)} tone="down" />
+        <CrosshairCell k="종" v={fmtKPrice(close)} strong />
+        <CrosshairCell k="거래량" v={fmtKVolume(volume)} />
+      </div>
+    </div>
+  );
+}
+
+function CrosshairCell({
+  k,
+  v,
+  tone,
+  strong,
+}: {
+  k: string;
+  v: string;
+  tone?: "up" | "down";
+  strong?: boolean;
+}) {
+  const tcls =
+    tone === "up"
+      ? "text-rose-300"
+      : tone === "down"
+        ? "text-sky-300"
+        : strong
+          ? "text-zinc-100"
+          : "text-zinc-300";
+  return (
+    <span className="flex items-baseline gap-1">
+      <span className="text-zinc-500">{k}</span>
+      <span className={tcls}>{v}</span>
+    </span>
+  );
+}