diff --git a/app.py b/app.py
index fd8b799..0374782 100644
--- a/app.py
+++ b/app.py
@@ -1,4 +1,4 @@
-import os, io, random, requests, openpyxl
+import os, io, random, requests, openpyxl, concurrent.futures
 from flask import Flask, render_template, request, jsonify, send_file
 
 app = Flask(__name__)
@@ -23,32 +23,28 @@ def tab_data(tab_id):
     return t, None
 
 
-def geocode(address):
-    try:
-        url = 'https://nominatim.openstreetmap.org/search'
-        params = {'q': address.strip(), 'format': 'json', 'limit': 1}
-        headers = {'User-Agent': 'MapinDrag/1.0'}
-        resp = requests.get(url, params=params, headers=headers, timeout=10)
-        if resp.ok and resp.json():
-            r = resp.json()[0]
-            return float(r['lat']), float(r['lon'])
-    except Exception:
-        pass
-    return None, None
-
+GEO_CACHE = {}
 
 def geocode_with_fallback(address):
-    lat, lng = geocode(f'{address}, 대한민국')
-    if lat is not None:
-        return lat, lng
-    lat, lng = geocode(f'서울특별시 용산구 {address}')
-    if lat is not None:
-        return lat, lng
-    lat, lng = geocode(f'용산구 {address}')
-    if lat is not None:
-        return lat, lng
+    if address in GEO_CACHE:
+        return GEO_CACHE[address]
+    try:
+        url = 'https://nominatim.openstreetmap.org/search'
+        params = {'q': address.strip(), 'format': 'json', 'limit': 1, 'countrycodes': 'kr'}
+        headers = {'User-Agent': 'MapinDrag/1.0'}
+        resp = requests.get(url, params=params, headers=headers, timeout=5)
+        if resp.ok:
+            data = resp.json()
+            if data:
+                lat, lng = float(data[0]['lat']), float(data[0]['lon'])
+                GEO_CACHE[address] = (lat, lng)
+                return lat, lng
+    except Exception:
+        pass
     jitter = random.uniform(-0.005, 0.005)
-    return YONGSAN_CENTER[0] + jitter, YONGSAN_CENTER[1] + jitter
+    result = (YONGSAN_CENTER[0] + jitter, YONGSAN_CENTER[1] + jitter)
+    GEO_CACHE[address] = result
+    return result
 
 
 def empty_tab(name):
@@ -73,9 +69,8 @@ def add_tab():
     tid = f'tab_{store["next_id"]}'
     store['next_id'] += 1
     store['tabs'][tid] = empty_tab(name)
-    if store['active_tab'] is None:
-        store['active_tab'] = tid
-    return jsonify({'id': tid, 'name': name})
+    store['active_tab'] = tid
+    return jsonify({'id': tid, 'name': name, 'activeTab': tid})
 
 
 @app.route('/api/tabs/rename', methods=['POST'])
@@ -149,7 +144,27 @@ def upload():
     file.save(path)
     wb = openpyxl.load_workbook(path, data_only=True)
 
-    workers, workplaces = [], []
+    workers, workplaces, all_addrs = [], [], set()
+    for sheet_name in wb.sheetnames:
+        ws = wb[sheet_name]
+        headers = [str(c.value or '').strip() for c in ws[1]]
+        if '희망사항' in headers:
+            idx = {h: i for i, h in enumerate(headers)}
+            for row in ws.iter_rows(min_row=2, values_only=True):
+                if not any(row): continue
+                name = str(row[idx.get('이름', 0)] or '').strip()
+                if name: all_addrs.add(str(row[idx.get('주소', 2)] or '').strip())
+        if '희망사항' not in headers:
+            idx = {h: i for i, h in enumerate(headers)}
+            for row in ws.iter_rows(min_row=2, values_only=True):
+                if not any(row): continue
+                name = str(row[idx.get('이름', 0)] or '').strip()
+                if name: all_addrs.add(str(row[idx.get('주소', 1)] or '').strip())
+
+    with concurrent.futures.ThreadPoolExecutor(max_workers=5) as exc:
+        geo_results = {a: exc.submit(geocode_with_fallback, a) for a in all_addrs}
+        geo_results = {a: f.result() for a, f in geo_results.items()}
+
     for sheet_name in wb.sheetnames:
         ws = wb[sheet_name]
         headers = [str(c.value or '').strip() for c in ws[1]]
@@ -157,17 +172,15 @@ def upload():
         if '희망사항' in headers:
             idx = {h: i for i, h in enumerate(headers)}
             for row in ws.iter_rows(min_row=2, values_only=True):
-                if not any(row):
-                    continue
+                if not any(row): continue
                 name = str(row[idx.get('이름', 0)] or '').strip()
-                if not name:
-                    continue
-                lat, lng = geocode_with_fallback(str(row[idx.get('주소', 2)] or '').strip())
+                if not name: continue
+                addr = str(row[idx.get('주소', 2)] or '').strip()
+                lat, lng = geo_results[addr]
                 workers.append({
-                    'id': f'w{len(workers)}',
-                    'name': name,
+                    'id': f'w{len(workers)}', 'name': name,
                     'hope': str(row[idx.get('희망사항', 1)] or '').strip(),
-                    'address': str(row[idx.get('주소', 2)] or '').strip(),
+                    'address': addr,
                     'dob': str(row[idx.get('생년월일', 3)] or '').strip(),
                     'phone': str(row[idx.get('연락처', 4)] or '').strip(),
                     'lat': lat, 'lng': lng,
@@ -176,17 +189,14 @@ def upload():
         if '희망사항' not in headers:
             idx = {h: i for i, h in enumerate(headers)}
             for row in ws.iter_rows(min_row=2, values_only=True):
-                if not any(row):
-                    continue
+                if not any(row): continue
                 name = str(row[idx.get('이름', 0)] or '').strip()
-                if not name:
-                    continue
-                lat, lng = geocode_with_fallback(str(row[idx.get('주소', 1)] or '').strip())
+                if not name: continue
+                addr = str(row[idx.get('주소', 1)] or '').strip()
+                lat, lng = geo_results[addr]
                 workplaces.append({
-                    'id': f'p{len(workplaces)}',
-                    'name': name,
-                    'address': str(row[idx.get('주소', 1)] or '').strip(),
-                    'lat': lat, 'lng': lng,
+                    'id': f'p{len(workplaces)}', 'name': name,
+                    'address': addr, 'lat': lat, 'lng': lng,
                 })
 
     t['workers'] = workers
diff --git a/templates/index.html b/templates/index.html
index b1bc14b..a261d61 100644
--- a/templates/index.html
+++ b/templates/index.html
@@ -115,8 +115,9 @@ async function addTab() {
     body: JSON.stringify({ name: name.trim() || undefined }),
   });
   tabDataCache[r.id] = { workers: [], workplaces: [], assignments: {} };
-  activeTabId = r.id;
-  await loadTabs();
+  activeTabId = r.activeTab;
+  render();
+  renderTabBar();
 }
 
 async function renameTab(e, tid) {