diff --git a/frontend/src/components/DashboardPage.tsx b/frontend/src/components/DashboardPage.tsx
index 0e21ea9..2e603f8 100644
--- a/frontend/src/components/DashboardPage.tsx
+++ b/frontend/src/components/DashboardPage.tsx
@@ -10,6 +10,7 @@ import {
   type ProcessMonitorDto,
   type SystemMonitorDto,
 } from '../utils/backendApi';
+import { formatUpbitKrwPrice } from '../utils/safeFormat';
 import DashboardGauge from './dashboard/DashboardGauge';
 import DashboardSegmentBar from './dashboard/DashboardSegmentBar';
 import DashboardSparkChart from './dashboard/DashboardSparkChart';
@@ -339,7 +340,7 @@ const DashboardPage: React.FC<Props> = ({ theme, onGoChart }) => {
                           <button type="button" className="gc-signal-main" onClick={() => onGoChart?.(s.market)}>
                             <strong>{buy ? 'BUY' : 'SELL'}</strong>
                             <span>{s.market.replace('KRW-', '')}</span>
-                            <span className="gc-signal-price">@ {s.price?.toLocaleString('ko-KR')}</span>
+                            <span className="gc-signal-price">@ {s.price != null ? formatUpbitKrwPrice(s.price) : ''}</span>
                           </button>
                           <span className="gc-signal-time">{s.createdAt?.slice(11, 16) ?? ''}</span>
                         </li>
diff --git a/frontend/src/components/DrawingCanvas.tsx b/frontend/src/components/DrawingCanvas.tsx
index 3a19954..9e0ee13 100644
--- a/frontend/src/components/DrawingCanvas.tsx
+++ b/frontend/src/components/DrawingCanvas.tsx
@@ -2,6 +2,7 @@ import React, { useRef, useEffect, useCallback, useState } from 'react';
 import type { ChartManager } from '../utils/ChartManager';
 import type { Drawing, DrawingPoint, DrawingToolId, Theme } from '../types';
 import { formatUnixDateTime } from '../utils/timezone';
+import { formatUpbitKrwPrice } from '../utils/safeFormat';
 
 // ─── Hit-test ──────────────────────────────────────────────────────────────
 const HIT_RADIUS = 7; // px (CSS 좌표)
@@ -1088,7 +1089,7 @@ function renderInfoLine(ctx: CanvasRenderingContext2D, d: Drawing, m: ChartManag
   ctx.strokeStyle = d.color; ctx.lineWidth = d.lineWidth ?? 1;
   ctx.beginPath(); ctx.moveTo(0, y); ctx.lineTo(cssW, y); ctx.stroke();
   const price = d.points[0].price;
-  const label = price >= 1000 ? price.toLocaleString('ko-KR') : price.toFixed(4);
+  const label = formatUpbitKrwPrice(price);
   ctx.font = 'bold 10px sans-serif';
   const tw = ctx.measureText(label).width + 8;
   ctx.fillStyle = d.color;
diff --git a/frontend/src/components/MarketPanel.tsx b/frontend/src/components/MarketPanel.tsx
index d928e27..54a1d17 100644
--- a/frontend/src/components/MarketPanel.tsx
+++ b/frontend/src/components/MarketPanel.tsx
@@ -13,6 +13,7 @@ import {
   getFavorites, saveFavorites, toggleFavorite,
   getHoldings, addHolding, removeHolding,
 } from '../utils/marketStorage';
+import { formatUpbitKrwPrice } from '../utils/safeFormat';
 // ─── 타입 ──────────────────────────────────────────────────────────────────
 type Tab = 'krw' | 'btc' | 'hold' | 'fav';
 type SortKey = 'name' | 'price' | 'change';
@@ -29,12 +30,7 @@ export interface MarketPanelProps {
 
 // ─── 가격 포맷 헬퍼 ────────────────────────────────────────────────────────
 function fmtKrw(price: number | null | undefined): string {
-  if (price == null || !isFinite(price)) return '-';
-  if (price >= 1_000_000) return price.toLocaleString('ko-KR', { maximumFractionDigits: 0 });
-  if (price >= 1_000)     return price.toLocaleString('ko-KR', { maximumFractionDigits: 0 });
-  if (price >= 1)         return price.toLocaleString('ko-KR', { maximumFractionDigits: 2 });
-  if (price >= 0.01)      return price.toFixed(4);
-  return price.toFixed(8);
+  return formatUpbitKrwPrice(price, '-');
 }
 
 function fmtUsd(krwPrice: number | null | undefined, rate: number): string {
diff --git a/frontend/src/components/OrderbookPanel.tsx b/frontend/src/components/OrderbookPanel.tsx
index 42f1228..aa8ddc4 100644
--- a/frontend/src/components/OrderbookPanel.tsx
+++ b/frontend/src/components/OrderbookPanel.tsx
@@ -7,12 +7,11 @@ import { formatNowClock, useDisplayTimezone } from '../utils/timezone';
 import type { OrderbookDisplayUnit, WsStatus } from '../hooks/useUpbitOrderbook';
 import type { RecentTrade } from '../hooks/useUpbitRecentTrades';
 import { getKoreanName } from '../utils/marketNameCache';
+import { formatUpbitKrwPrice } from '../utils/safeFormat';
 
 function fmtPrice(p: number): string {
   if (p == null || !isFinite(p)) return '-';
-  if (p >= 1_000) return p.toLocaleString('ko-KR', { maximumFractionDigits: 0 });
-  if (p >= 1) return p.toFixed(2);
-  return p.toFixed(6);
+  return formatUpbitKrwPrice(p, '-');
 }
 
 function fmtSize(s: number): string {
diff --git a/frontend/src/components/TradeAlertModal.tsx b/frontend/src/components/TradeAlertModal.tsx
index 6ae422d..95d4cc2 100644
--- a/frontend/src/components/TradeAlertModal.tsx
+++ b/frontend/src/components/TradeAlertModal.tsx
@@ -3,6 +3,7 @@ import React, { useState } from 'react';
 import { useDraggablePanel } from '../hooks/useDraggablePanel';
 import { placePaperOrder, placeLiveOrder, loadLiveSummary } from '../utils/backendApi';
 import { formatSignalTime } from '../utils/tradeSignalDisplay';
+import { formatUpbitKrwPrice } from '../utils/safeFormat';
 import { TRADE_BUY_COLOR, TRADE_SELL_COLOR } from '../utils/tradeSignalColors';
 import { useTradeAlertTimeFormat } from '../utils/tradeAlertTimeFormat';
 
@@ -30,7 +31,7 @@ interface Props {
 }
 
 const fmt = (n: number): string =>
-  n > 0 ? n.toLocaleString('ko-KR', { maximumFractionDigits: 0 }) : '0';
+  n > 0 ? formatUpbitKrwPrice(n, '0') : '0';
 
 
 function execLabel(type?: string, candleType?: string): string {
diff --git a/frontend/src/components/TradeOrderPanel.tsx b/frontend/src/components/TradeOrderPanel.tsx
index c198fad..dad99cf 100644
--- a/frontend/src/components/TradeOrderPanel.tsx
+++ b/frontend/src/components/TradeOrderPanel.tsx
@@ -7,7 +7,7 @@ import { getKoreanName } from '../utils/marketNameCache';
 import { MarketSearchPanel } from './MarketSearchPanel';
 import type { TradeOrderFillRequest } from '../types';
 import { placePaperOrder } from '../utils/backendApi';
-import { coerceFiniteNumber } from '../utils/safeFormat';
+import { coerceFiniteNumber, formatUpbitKrwPrice, upbitKrwTickSize } from '../utils/safeFormat';
 
 export type OrderKind = 'limit' | 'market' | 'stop_limit';
 
@@ -39,7 +39,7 @@ export interface TradeOrderPanelProps {
 
 export function fmtKrw(n: number): string {
   if (!Number.isFinite(n)) return '0';
-  return Math.round(n).toLocaleString('ko-KR');
+  return formatUpbitKrwPrice(n, '0');
 }
 
 function parseNum(s: string): number {
@@ -47,11 +47,19 @@ function parseNum(s: string): number {
   return Number.isFinite(v) ? v : 0;
 }
 
-/** KRW 가격: 숫자만 허용, 천 단위 쉼표 표시 */
+/** KRW 가격: 숫자·소수점(필요 시)만 허용, 업비트 규칙으로 표시 */
 function sanitizePriceInput(raw: string): string {
-  const digits = raw.replace(/\D/g, '');
-  if (!digits) return '';
-  return Number(digits).toLocaleString('ko-KR');
+  const cleaned = raw.replace(/[^\d.]/g, '');
+  if (!cleaned) return '';
+  const n = Number(cleaned);
+  if (!Number.isFinite(n)) return '';
+  return formatUpbitKrwPrice(n, cleaned);
+}
+
+/** 현재 가격에 맞는 호가 단위만큼 증감 */
+export function stepPriceByTick(price: number, direction: 1 | -1): number {
+  const tick = upbitKrwTickSize(price);
+  return Math.round((price + direction * tick) / tick) * tick;
 }
 
 /** 주문 수량: 숫자와 소수점(1개)만 허용 */
diff --git a/frontend/src/components/TradingChart.tsx b/frontend/src/components/TradingChart.tsx
index 3809938..1d5ecf3 100644
--- a/frontend/src/components/TradingChart.tsx
+++ b/frontend/src/components/TradingChart.tsx
@@ -2,6 +2,7 @@ import React, { useRef, useEffect, useLayoutEffect, useState, useCallback } from
 import type { MouseEventParams, Time } from 'lightweight-charts';
 import type { OHLCVBar, ChartType, Theme, IndicatorConfig, LegendData, Drawing, ChartMode, Timeframe } from '../types';
 import { ChartManager } from '../utils/ChartManager';
+import { formatUpbitKrwPrice } from '../utils/safeFormat';
 import { useChartTimeFormat } from '../utils/chartTimeFormat';
 import { setIndicatorChartContext } from '../utils/indicatorRegistry';
 import { DISPLAY_COUNT } from '../hooks/useUpbitData';
@@ -1675,8 +1676,7 @@ const TradingChart: React.FC<TradingChartProps> = ({
     container.style.cursor = isHit ? 'pointer' : '';
   }, []);
 
-  const fmtCtxPrice = (p: number) =>
-    p >= 1000 ? Math.round(p).toLocaleString('ko-KR') : p.toFixed(p >= 1 ? 2 : 6);
+  const fmtCtxPrice = (p: number) => formatUpbitKrwPrice(p);
 
   const closeCtxAndRequest = useCallback((side: 'buy' | 'sell') => {
     if (!ctxMenu || !market) return;
diff --git a/frontend/src/components/analysisReport/AnalysisReportViews.tsx b/frontend/src/components/analysisReport/AnalysisReportViews.tsx
index d42bccf..38a2e13 100644
--- a/frontend/src/components/analysisReport/AnalysisReportViews.tsx
+++ b/frontend/src/components/analysisReport/AnalysisReportViews.tsx
@@ -19,17 +19,18 @@ import {
   drawdownSeries,
 } from '../../utils/analysisReportMetrics';
 import { repairUtf8Mojibake } from '../../utils/textEncoding';
+import { formatUpbitKrwPrice } from '../../utils/safeFormat';
 
 /* ── 포맷 유틸 ── */
 const pct   = (v: number, dec = 2) => `${v >= 0 ? '+' : ''}${(v * 100).toFixed(dec)}%`;
 const pctAbs= (v: number, dec = 1) => `${(v * 100).toFixed(dec)}%`;
 const num   = (v: number, dec = 2) => (isFinite(v) ? v.toFixed(dec) : '—');
-const wonFmt= (v: number) => {
+const wonFmt = (v: number) => {
   const abs = Math.abs(v);
   const sign = v < 0 ? '-' : v > 0 ? '+' : '';
   if (abs >= 1e8) return `${sign}${(abs / 1e8).toFixed(1)}억`;
   if (abs >= 1e4) return `${sign}${(abs / 1e4).toFixed(0)}만`;
-  return `${sign}${abs.toLocaleString('ko-KR')}원`;
+  return `${sign}${formatUpbitKrwPrice(abs, '0')}원`;
 };
 const colorCls = (v: number) => (v > 0 ? 'up' : v < 0 ? 'down' : '');
 
@@ -617,8 +618,8 @@ function LogsView({ ctx }: { ctx: AnalysisReportContext }) {
                 <td>{r.dateTime}</td>
                 <td className="qcc-sym">{r.symbol.replace('KRW-', 'KRW-')}</td>
                 <td className="qcc-side">{r.side}</td>
-                <td className="qcc-num">{r.entryPrice.toLocaleString('ko-KR')}</td>
-                <td className="qcc-num">{r.exitPrice.toLocaleString('ko-KR')}</td>
+                <td className="qcc-num">{formatUpbitKrwPrice(r.entryPrice)}</td>
+                <td className="qcc-num">{formatUpbitKrwPrice(r.exitPrice)}</td>
                 <td className="qcc-num">{r.qty.toFixed(3)}</td>
                 <td className={r.pnlPct >= 0 ? 'up' : 'down'}>{r.pnlPct >= 0 ? '+' : ''}{r.pnlPct.toFixed(1)}%</td>
                 <td className="qcc-dur">{r.durationSec > 0 ? fmtDuration(r.durationSec) : '—'}</td>
@@ -658,7 +659,7 @@ function AllocationView({ ctx }: { ctx: AnalysisReportContext }) {
               <span className="qcc-alloc-dot" style={{ background: sl.color }} />
               <span className="qcc-alloc-sym">{sl.symbol.replace('KRW-', 'KRW-')}</span>
               <span className="qcc-alloc-pct">{(sl.pct * 100).toFixed(2)}%</span>
-              <span className="qcc-alloc-krw">₩{Math.round(sl.capitalKrw).toLocaleString('ko-KR')}</span>
+              <span className="qcc-alloc-krw">₩{formatUpbitKrwPrice(sl.capitalKrw)}</span>
             </div>
           ))}
         </div>
diff --git a/frontend/src/components/backtest/BacktestKpiPanel.tsx b/frontend/src/components/backtest/BacktestKpiPanel.tsx
index fe23787..8e7b40f 100644
--- a/frontend/src/components/backtest/BacktestKpiPanel.tsx
+++ b/frontend/src/components/backtest/BacktestKpiPanel.tsx
@@ -3,6 +3,7 @@ import type { BacktestAnalysis } from '../../utils/backendApi';
 import BacktestSparkline from './BacktestSparkline';
 import type { EquityPoint } from '../../utils/backtestEquity';
 import { krw, pct, pctAbs } from '../../utils/backtestUiUtils';
+import { formatUpbitKrwPrice } from '../../utils/safeFormat';
 
 interface Props {
   analysis: BacktestAnalysis | null;
@@ -21,7 +22,7 @@ interface Props {
 const num = (v: number, dec = 2) => (isFinite(v) ? v.toFixed(dec) : '–');
 
 const fmtWon = (v: number) =>
-  isFinite(v) ? `₩${Math.round(v).toLocaleString('ko-KR')}` : '–';
+  isFinite(v) ? `₩${formatUpbitKrwPrice(v, '–')}` : '–';
 
 function MetricCell({
   label,
diff --git a/frontend/src/components/paper/PaperCompactOrderbook.tsx b/frontend/src/components/paper/PaperCompactOrderbook.tsx
index dafc85f..b3b6014 100644
--- a/frontend/src/components/paper/PaperCompactOrderbook.tsx
+++ b/frontend/src/components/paper/PaperCompactOrderbook.tsx
@@ -1,6 +1,6 @@
 import React, { memo } from 'react';
 import { useUpbitOrderbook } from '../../hooks/useUpbitOrderbook';
-import { coerceFiniteNumber, safeToFixed } from '../../utils/safeFormat';
+import { coerceFiniteNumber, safeToFixed, formatUpbitKrwPrice } from '../../utils/safeFormat';
 
 interface Props {
   market: string;
@@ -14,8 +14,7 @@ interface Props {
 
 function fmtPrice(p: unknown): string {
   const n = coerceFiniteNumber(p);
-  if (n == null) return '-';
-  return n >= 1000 ? n.toLocaleString('ko-KR', { maximumFractionDigits: 0 }) : safeToFixed(n, 4);
+  return formatUpbitKrwPrice(n, '-');
 }
 
 function fmtSize(s: unknown): string {
diff --git a/frontend/src/components/trendSearch/TrendSearchResultsGrid.tsx b/frontend/src/components/trendSearch/TrendSearchResultsGrid.tsx
index b5c36f9..21394d3 100644
--- a/frontend/src/components/trendSearch/TrendSearchResultsGrid.tsx
+++ b/frontend/src/components/trendSearch/TrendSearchResultsGrid.tsx
@@ -1,5 +1,6 @@
 import React, { useMemo } from 'react';
 import type { TrendSearchResultDto } from '../../utils/trendSearchApi';
+import { formatUpbitKrwPrice } from '../../utils/safeFormat';
 
 interface Props {
   results: TrendSearchResultDto[];
@@ -10,9 +11,7 @@ interface Props {
 }
 
 function fmtPrice(n: number): string {
-  if (n >= 1_000_000) return n.toLocaleString('ko-KR', { maximumFractionDigits: 0 });
-  if (n >= 100) return n.toLocaleString('ko-KR', { maximumFractionDigits: 0 });
-  return n.toLocaleString('ko-KR', { maximumFractionDigits: 4 });
+  return formatUpbitKrwPrice(n, '-');
 }
 
 function fmtPct(n: number): string {
diff --git a/frontend/src/components/virtual/VirtualTargetQuote.tsx b/frontend/src/components/virtual/VirtualTargetQuote.tsx
index b63aba9..c43a49e 100644
--- a/frontend/src/components/virtual/VirtualTargetQuote.tsx
+++ b/frontend/src/components/virtual/VirtualTargetQuote.tsx
@@ -1,15 +1,10 @@
 import React, { memo, useEffect, useRef, useState } from 'react';
 import type { ChangeDir, TickerData } from '../../hooks/useMarketTicker';
-import { coerceFiniteNumber, safePercentFromRate, safeToFixed } from '../../utils/safeFormat';
+import { coerceFiniteNumber, safePercentFromRate, formatUpbitKrwPrice } from '../../utils/safeFormat';
 
 function fmtKrw(price: number | null | undefined | unknown): string {
   const p = coerceFiniteNumber(price);
-  if (p == null) return '-';
-  if (p >= 1_000_000) return p.toLocaleString('ko-KR', { maximumFractionDigits: 0 });
-  if (p >= 1_000) return p.toLocaleString('ko-KR', { maximumFractionDigits: 0 });
-  if (p >= 1) return p.toLocaleString('ko-KR', { maximumFractionDigits: 2 });
-  if (p >= 0.01) return safeToFixed(p, 4, '-');
-  return safeToFixed(p, 8, '-');
+  return formatUpbitKrwPrice(p, '-');
 }
 
 function fmtPct(rate: number | null | undefined | unknown): string {
diff --git a/frontend/src/utils/ChartManager.ts b/frontend/src/utils/ChartManager.ts
index 0226511..011d0c9 100644
--- a/frontend/src/utils/ChartManager.ts
+++ b/frontend/src/utils/ChartManager.ts
@@ -25,6 +25,7 @@ import { BollingerBandFillPrimitive } from './BollingerBandFillPrimitive';
 import { resolveBbBandBackground } from './bollingerConfig';
 import type { OHLCVBar, ChartType, Theme, IndicatorConfig, Timeframe } from '../types';
 import { formatChartAxisPrice, formatIndicatorAxisPrice } from './dataGenerator';
+import { formatUpbitKrwPrice } from './safeFormat';
 import { TRADE_BUY_COLOR, TRADE_SELL_COLOR } from './tradeSignalColors';
 import {
   DEFAULT_CHART_TIME_FORMAT,
@@ -1271,7 +1272,7 @@ export class ChartManager {
           : buy ? '매수'
           : '매도';
         const text = showPrice
-          ? `${label} : ${s.price.toLocaleString()}`
+          ? `${label} : ${formatUpbitKrwPrice(s.price)}`
           : label;
         return {
           time:     s.time,
@@ -1304,7 +1305,7 @@ export class ChartManager {
       const buy  = m.signal === 'BUY';
       const label = buy ? '매수' : '매도';
       const text = showPrice
-        ? `${label} : ${m.price.toLocaleString()}`
+        ? `${label} : ${formatUpbitKrwPrice(m.price)}`
         : label;
       return {
         time:     m.time,
@@ -1988,7 +1989,7 @@ export class ChartManager {
     if (!this.mainSeries) return;
     const line = this.mainSeries.createPriceLine({
       price, color: '#FFB300', lineWidth: 1, lineStyle: LineStyle.Dashed,
-      axisLabelVisible: true, title: label || `Alert ${price.toFixed(2)}`,
+      axisLabelVisible: true, title: label || `Alert ${formatUpbitKrwPrice(price)}`,
     });
     this.alertEntries.push({ price, label, line });
   }
@@ -2051,7 +2052,7 @@ export class ChartManager {
         this.drawingPoints = [];
       } else if (tool === 'trendline' && this.drawingPoints.length === 2) {
         const [p1, p2] = this.drawingPoints;
-        const l = this.mainSeries.createPriceLine({ price: (p1.price + p2.price) / 2, color: '#2962FF', lineWidth: 1, lineStyle: LineStyle.Solid, axisLabelVisible: false, title: `${p1.price.toFixed(2)}→${p2.price.toFixed(2)}` });
+        const l = this.mainSeries.createPriceLine({ price: (p1.price + p2.price) / 2, color: '#2962FF', lineWidth: 1, lineStyle: LineStyle.Solid, axisLabelVisible: false, title: `${formatUpbitKrwPrice(p1.price)}→${formatUpbitKrwPrice(p2.price)}` });
         this.drawingLines.push(l);
         this.drawingPoints = [];
       } else if (tool === 'measure' && this.drawingPoints.length === 2) {
diff --git a/frontend/src/utils/backtestUiUtils.ts b/frontend/src/utils/backtestUiUtils.ts
index 5498c09..92cbefa 100644
--- a/frontend/src/utils/backtestUiUtils.ts
+++ b/frontend/src/utils/backtestUiUtils.ts
@@ -1,4 +1,5 @@
 import type { ChartType, Timeframe } from '../types';
+import { formatUpbitKrwPrice } from './safeFormat';
 
 export function toUpbitMarket(symbol: string): string {
   return symbol.startsWith('KRW-') ? symbol : `KRW-${symbol}`;
@@ -79,8 +80,11 @@ export const pct = (v: number, dec = 1) =>
 export const pctAbs = (v: number, dec = 0) =>
   isFinite(v) ? `${(v * 100).toFixed(dec)}%` : '0%';
 
-export const krw = (v: number) =>
-  isFinite(v) ? `${v >= 0 ? '+' : ''}₩${Math.round(v).toLocaleString()}` : '–';
+export const krw = (v: number) => {
+  if (!isFinite(v)) return '–';
+  const sign = v >= 0 ? '+' : '-';
+  return `${sign}₩${formatUpbitKrwPrice(Math.abs(v), '0')}`;
+};
 
 const TF_SEC: Record<string, number> = {
   '1m': 60, '3m': 180, '5m': 300, '10m': 600, '15m': 900, '30m': 1800,
diff --git a/frontend/src/utils/chartLiveQuote.ts b/frontend/src/utils/chartLiveQuote.ts
index 48f11b4..6f3f922 100644
--- a/frontend/src/utils/chartLiveQuote.ts
+++ b/frontend/src/utils/chartLiveQuote.ts
@@ -3,6 +3,7 @@
  */
 import type { TickerData } from '../hooks/useMarketTicker';
 import type { OHLCVBar } from '../types';
+import { formatUpbitKrwPrice } from './safeFormat';
 
 export interface ChartLiveQuote {
   price: number | null;
@@ -41,7 +42,7 @@ export function resolveChartLiveQuote(
 
 export function formatChartLivePrice(price: number | null): string {
   if (price == null || !Number.isFinite(price)) return '—';
-  return `${Math.round(price).toLocaleString('ko-KR')} KRW`;
+  return `${formatUpbitKrwPrice(price)} KRW`;
 }
 
 export function formatChartLiveChangePct(changePct: number | null): string {
diff --git a/frontend/src/utils/dataGenerator.ts b/frontend/src/utils/dataGenerator.ts
index 85deb92..06de338 100644
--- a/frontend/src/utils/dataGenerator.ts
+++ b/frontend/src/utils/dataGenerator.ts
@@ -1,5 +1,6 @@
 import type { OHLCVBar, Timeframe } from '../types';
 import { formatUnixForChart } from './timezone';
+import { formatUpbitKrwPrice } from './safeFormat';
 
 export const SYMBOLS = [
   'BTCUSD','ETHUSD','BNBUSD','SOLUSD','ADAUSD',
@@ -82,25 +83,22 @@ export function generateBars(symbol: string, timeframe: Timeframe): OHLCVBar[] {
 }
 
 export function formatPrice(price: number): string {
-  if (price >= 10000) return price.toLocaleString('en-US', { minimumFractionDigits: 0, maximumFractionDigits: 0 });
-  if (price >= 100)   return price.toLocaleString('en-US', { minimumFractionDigits: 2, maximumFractionDigits: 2 });
-  if (price >= 1)     return price.toLocaleString('en-US', { minimumFractionDigits: 3, maximumFractionDigits: 4 });
-  return price.toLocaleString('en-US', { minimumFractionDigits: 4, maximumFractionDigits: 6 });
+  return formatUpbitKrwPrice(price, String(price));
 }
 
-/** 실시간 차트 우측 가격축·크로스헤어·시리즈 라벨 (KRW 주가 — 소수점 없음) */
+/**
+ * 실시간 차트 우측 가격축·크로스헤어·시리즈 라벨 — 업비트 KRW 가격 표시 규칙 적용.
+ * LightweightCharts formatter 콜백으로 사용되므로 항상 string 반환.
+ */
 export function formatChartAxisPrice(price: number): string {
   if (!Number.isFinite(price)) return String(price);
-  return Math.round(price).toLocaleString('en-US', {
-    minimumFractionDigits: 0,
-    maximumFractionDigits: 0,
-  });
+  return formatUpbitKrwPrice(price, String(price));
 }
 
 /** 보조지표 pane 우측 가격축·시리즈 라벨 (소수점 2자리 고정) */
 export function formatIndicatorAxisPrice(price: number): string {
   if (!Number.isFinite(price)) return String(price);
-  return price.toLocaleString('en-US', {
+  return price.toLocaleString('ko-KR', {
     minimumFractionDigits: 2,
     maximumFractionDigits: 2,
   });
diff --git a/frontend/src/utils/safeFormat.ts b/frontend/src/utils/safeFormat.ts
index a9b299f..dd4b4e6 100644
--- a/frontend/src/utils/safeFormat.ts
+++ b/frontend/src/utils/safeFormat.ts
@@ -1,3 +1,96 @@
+/**
+ * 업비트 KRW 마켓 가격 표시 규칙 (2024년 개정 기준)
+ *
+ * 가격대 별 호가 단위:
+ *   ≥ 2,000,000원 : 1,000원 단위 (소수점 없음)   예) 92,133,000
+ *   ≥ 200,000원   :   100원 단위 (소수점 없음)   예)    234,100
+ *   ≥ 10,000원    :    10원 단위 (소수점 없음)   예)     23,450
+ *   ≥ 100원       :     1원 단위 (소수점 없음)   예)      1,234  / 452
+ *   ≥ 10원        :   0.1원 단위 (소수점 1자리)  예)       45.3
+ *   ≥ 1원         :  0.01원 단위 (소수점 2자리)  예)        4.53
+ *   ≥ 0.1원       : 0.001원 단위 (소수점 3자리)  예)        0.453
+ *   < 0.1원       : 0.0001원 단위 (소수점 4자리) 예)        0.0123
+ *
+ * 주의: 100~1,000원 구간은 2024년 이후 1원 단위(소수점 없음)로 환원됨.
+ */
+export function formatUpbitKrwPrice(
+  price: number | null | undefined,
+  fallback = '—',
+): string {
+  if (price == null || !Number.isFinite(price)) return fallback;
+  const abs = Math.abs(price);
+
+  if (abs >= 2_000_000) {
+    // 1,000원 단위
+    return (Math.round(price / 1000) * 1000).toLocaleString('ko-KR', {
+      maximumFractionDigits: 0,
+    });
+  }
+  if (abs >= 200_000) {
+    // 100원 단위
+    return (Math.round(price / 100) * 100).toLocaleString('ko-KR', {
+      maximumFractionDigits: 0,
+    });
+  }
+  if (abs >= 10_000) {
+    // 10원 단위
+    return (Math.round(price / 10) * 10).toLocaleString('ko-KR', {
+      maximumFractionDigits: 0,
+    });
+  }
+  if (abs >= 100) {
+    // 1원 단위 (소수점 없음) — 100~10,000원 구간
+    return Math.round(price).toLocaleString('ko-KR', {
+      maximumFractionDigits: 0,
+    });
+  }
+  if (abs >= 10) {
+    // 0.1원 단위 (소수점 1자리)
+    return (Math.round(price * 10) / 10).toLocaleString('ko-KR', {
+      minimumFractionDigits: 1,
+      maximumFractionDigits: 1,
+    });
+  }
+  if (abs >= 1) {
+    // 0.01원 단위 (소수점 2자리)
+    return (Math.round(price * 100) / 100).toLocaleString('ko-KR', {
+      minimumFractionDigits: 2,
+      maximumFractionDigits: 2,
+    });
+  }
+  if (abs >= 0.1) {
+    // 0.001원 단위 (소수점 3자리)
+    return (Math.round(price * 1000) / 1000).toLocaleString('ko-KR', {
+      minimumFractionDigits: 3,
+      maximumFractionDigits: 3,
+    });
+  }
+  if (abs > 0) {
+    // 0.0001원 단위 (소수점 4자리)
+    return (Math.round(price * 10000) / 10000).toLocaleString('ko-KR', {
+      minimumFractionDigits: 4,
+      maximumFractionDigits: 4,
+    });
+  }
+  return '0';
+}
+
+/**
+ * 업비트 KRW 가격의 최소 호가 단위(tick size)를 반환한다.
+ * LightweightCharts priceFormat.minMove 또는 주문 입력 스텝 계산에 사용.
+ */
+export function upbitKrwTickSize(price: number): number {
+  const abs = Math.abs(price);
+  if (abs >= 2_000_000) return 1000;
+  if (abs >= 200_000)   return 100;
+  if (abs >= 10_000)    return 10;
+  if (abs >= 100)       return 1;
+  if (abs >= 10)        return 0.1;
+  if (abs >= 1)         return 0.01;
+  if (abs >= 0.1)       return 0.001;
+  return 0.0001;
+}
+
 /**
  * API·JSON·WebSocket에서 문자열로 올 수 있는 숫자를 안전하게 처리
  */
diff --git a/frontend/src/utils/tradeSignalDisplay.ts b/frontend/src/utils/tradeSignalDisplay.ts
index c655564..7b42c0d 100644
--- a/frontend/src/utils/tradeSignalDisplay.ts
+++ b/frontend/src/utils/tradeSignalDisplay.ts
@@ -1,6 +1,7 @@
 /**
  * 매매 시그널 알림 표시용 포맷·라벨
  */
+import { formatUpbitKrwPrice } from './safeFormat';
 import { formatUnixWithChartPattern, splitChartTimePattern } from './chartTimeFormat';
 import { getKoreanName } from './marketNameCache';
 import { getTradeAlertTimeFormat } from './tradeAlertTimeFormat';
@@ -27,7 +28,7 @@ export function parseMarket(market: string) {
 
 export function formatSignalPrice(price: number): string {
   if (!Number.isFinite(price) || price <= 0) return '—';
-  return `₩${price.toLocaleString('ko-KR', { maximumFractionDigits: 0 })}`;
+  return `₩${formatUpbitKrwPrice(price, '—')}`;
 }
 
 export function formatSignalTime(unixSec: number, withDate = true): string {