diff --git a/src/hudLocalityFormat.js b/src/hudLocalityFormat.js
index 84278564b..b508f8d59 100644
--- a/src/hudLocalityFormat.js
+++ b/src/hudLocalityFormat.js
@@ -15,7 +15,9 @@ export function hudQuantity(value, unit, digits = 0) {
     minimumFractionDigits: digits,
     maximumFractionDigits: digits,
   });
-  return `${number}${unitLabel(unit).toUpperCase()}`;
+  const label = unitLabel(unit);
+  if (getLocale() === 'zh-CN') return label ? `${number} ${label}` : number;
+  return `${number}${label.toUpperCase()}`;
 }
 
 /** One hemisphere-tagged coordinate, e.g. `21.33N` / `21,33С`. */
diff --git a/src/i18n/locales/es.json b/src/i18n/locales/es.json
index cbba42e0e..c26430fe7 100644
--- a/src/i18n/locales/es.json
+++ b/src/i18n/locales/es.json
@@ -2941,5 +2941,7 @@
   "hemisphere|N": "N",
   "hemisphere|S": "S",
   "hemisphere|E": "E",
-  "hemisphere|W": "O"
+  "hemisphere|W": "O",
+  "OK": "OK",
+  "{category} ({count})": "{category} ({count})"
 }
diff --git a/src/i18n/locales/ru.json b/src/i18n/locales/ru.json
index dcd6ef20b..dadea1a42 100644
--- a/src/i18n/locales/ru.json
+++ b/src/i18n/locales/ru.json
@@ -3008,5 +3008,7 @@
   "hemisphere|N": "С",
   "hemisphere|S": "Ю",
   "hemisphere|E": "В",
-  "hemisphere|W": "З"
+  "hemisphere|W": "З",
+  "OK": "НОРМА",
+  "{category} ({count})": "{category} ({count})"
 }
diff --git a/src/i18n/locales/zh-CN.json b/src/i18n/locales/zh-CN.json
index 8b5240e12..6b815f545 100644
--- a/src/i18n/locales/zh-CN.json
+++ b/src/i18n/locales/zh-CN.json
@@ -2807,5 +2807,7 @@
   "Gemini interrupted input exceeded its buffer or wait limit. Start voice again.": "Gemini 被打断的输入超出了缓冲区或等待上限。请重新启动语音。",
   "Gemini Live connection is expiring. Start voice again for a new conversation.": "Gemini Live 连接即将到期。请重新启动语音以开始新对话。",
   "Gemini voice sessions have a time limit. When a session expires, start voice again for a new conversation.": "Gemini 语音会话有时长限制。会话到期后，请重新启动语音以开始新对话。",
-  "Show the street-level view full screen (Esc shrinks it)": "全屏显示街景视图（按 Esc 缩小）"
+  "Show the street-level view full screen (Esc shrinks it)": "全屏显示街景视图（按 Esc 缩小）",
+  "OK": "正常",
+  "{category} ({count})": "{category}（{count}）"
 }
diff --git a/src/i18n/same-as-english.json b/src/i18n/same-as-english.json
index 821b154b9..c331cd070 100644
--- a/src/i18n/same-as-english.json
+++ b/src/i18n/same-as-english.json
@@ -63,6 +63,7 @@
     "NVG",
     "Noir",
     "Normal",
+    "OK",
     "POS: {time}Z",
     "Plan",
     "Pop",
diff --git a/src/i18n/zh-CN-display.test.mjs b/src/i18n/zh-CN-display.test.mjs
new file mode 100644
index 000000000..b9e55058d
--- /dev/null
+++ b/src/i18n/zh-CN-display.test.mjs
@@ -0,0 +1,106 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { setLocale, t } from './index.js';
+import { hudQuantity, LOCALIZED_LOCALITY } from '../hudLocalityFormat.js';
+import { formatCockpitDistance } from '../ui/cockpitPresentation.js';
+import { cctvSourceStatusLabel } from '../ui/cctvFrames.js';
+import { READOUT_WORDS } from '../layers/recentImagery/display.js';
+import { createModel } from '../layers/firms/model.js';
+import { createQueries } from '../layers/firms/queries.js';
+import { renderRadioState } from '../ui/radioPresentation.js';
+
+test('Chinese HUD and cockpit units keep their case without spacing coordinates', () => {
+  try {
+    setLocale('zh-CN');
+    assert.equal(hudQuantity(0, 'km'), '0 km');
+    assert.equal(hudQuantity(2069, 'km', 1), '2069.0 km');
+    assert.equal(formatCockpitDistance(14000), '14\u00a0km');
+    assert.equal(LOCALIZED_LOCALITY.sector({ latDeg: 21.33, lonDeg: -77.5 }),
+      '扇区 21.33N 77.50W');
+    setLocale('en');
+    assert.equal(hudQuantity(0, 'km'), '0KM');
+    assert.equal(hudQuantity(2069, 'km', 1), '2069.0KM');
+    assert.equal(formatCockpitDistance(14000), '14\u00a0KM');
+  } finally {
+    setLocale('en');
+  }
+});
+
+test('FIRMS stale cache age uses localized durations while English stays compact', () => {
+  const now = Date.now();
+  const layerState = { _stale: true };
+  const components = {
+    model: createModel({ services: { anchors: {} } }),
+  };
+  const { methods } = createQueries({ layerState, components, config: {} });
+  try {
+    for (const [hours, zh, en] of [[0.5, '不到 1 小时', '<1h'], [2, '2 小时', '2h'], [72, '3 天', '3d']]) {
+      layerState._lastUpdate = now - hours * 3600000;
+      setLocale('zh-CN');
+      const expected = t('STALE · cached {age}', { age: zh });
+      assert.equal(methods.getStats().loadingLabel, expected);
+      assert.equal(methods.getStats().error, expected);
+      setLocale('en');
+      assert.equal(methods.getStats().loadingLabel, `STALE · cached ${en}`);
+    }
+  } finally {
+    setLocale('en');
+  }
+});
+
+test('Recent Imagery spaces numeric Chinese ages and retains natural relative dates', () => {
+  try {
+    setLocale('zh-CN');
+    assert.equal(READOUT_WORDS.daysAgo(9), '9 天前');
+    assert.equal(READOUT_WORDS.daysAgo(0), '今天');
+    assert.equal(READOUT_WORDS.daysAgo(1), '昨天');
+    setLocale('en');
+    assert.equal(READOUT_WORDS.daysAgo(9), '9 days ago');
+    assert.equal(READOUT_WORDS.daysAgo(0), 'today');
+  } finally {
+    setLocale('en');
+  }
+});
+
+test('CCTV translates the healthy status and preserves unknown provider codes', () => {
+  try {
+    for (const [locale, expected] of [['zh-CN', '正常'], ['ru', 'НОРМА'], ['es', 'OK'], ['en', 'OK']]) {
+      setLocale(locale);
+      assert.equal(cctvSourceStatusLabel('ok'), expected);
+      assert.equal(cctvSourceStatusLabel('CUSTOM'), 'CUSTOM');
+    }
+  } finally {
+    setLocale('en');
+  }
+});
+
+test('radio option text and accessible name use the same localized parentheses', () => {
+  const originalDocument = globalThis.document;
+  const element = () => ({
+    style: {}, dataset: {}, attributes: {},
+    classList: { contains: () => true, toggle() {} },
+    setAttribute(name, value) { this.attributes[name] = value; },
+    replaceChildren(...children) { this.children = children; },
+  });
+  globalThis.document = { createElement: element, getElementById: () => null };
+  try {
+    for (const [locale, label, expected] of [['zh-CN', '全部', '全部（750）'], ['en', 'All', 'All (750)']]) {
+      setLocale(locale);
+      const host = {
+        _radioPanel: element(), _radioFilter: element(),
+        _syncContextRadioLauncherState() {},
+        actions: { getLifecycle: () => null, scheduleLayout() {} },
+      };
+      renderRadioState.call(host, {
+        enabled: true, categories: [{ id: 'all', label, count: 750, color: '' }],
+        filter: 'all', filteredCount: 750, stationCount: 750, volume: 1,
+      });
+      const option = host._radioFilter.children[0];
+      assert.equal(option.textContent, `● ${expected}`);
+      assert.equal(option.attributes['aria-label'], expected);
+    }
+  } finally {
+    globalThis.document = originalDocument;
+    setLocale('en');
+  }
+});
diff --git a/src/layers/firms/model.js b/src/layers/firms/model.js
index 3a1df327b..226c32286 100644
--- a/src/layers/firms/model.js
+++ b/src/layers/firms/model.js
@@ -591,6 +591,7 @@ export function createModel({
     formatLatLon,
     formatFrp,
     formatAge,
+    formatAgeLabel,
     formatAgoMinutes,
     confidenceBucket,
   };
diff --git a/src/layers/firms/queries.js b/src/layers/firms/queries.js
index a7d22589e..c4a793f9d 100644
--- a/src/layers/firms/queries.js
+++ b/src/layers/firms/queries.js
@@ -64,7 +64,8 @@ export function createQueries({
       const staleText = layerState._lastUpdate
         ? t('STALE · cached {age}', {
             age:
-              components.model.formatAge(now - layerState._lastUpdate) || '<1h',
+              components.model.formatAgeLabel(now - layerState._lastUpdate) ||
+              t('<1h', { context: 'age' }),
           })
         : t('STALE');
       let loadingLabel = '';
diff --git a/src/layers/recentImagery/display.js b/src/layers/recentImagery/display.js
index 5b2b5ce39..5c18d8b3f 100644
--- a/src/layers/recentImagery/display.js
+++ b/src/layers/recentImagery/display.js
@@ -3,7 +3,12 @@
  * day's readout. The model (`model.js`) stays English and i18n-free because AI
  * tool services import it outside the browser; this module is page-only.
  */
-import { formatDate, formatRelativeTime, t } from '../../i18n/index.js';
+import {
+  formatDate,
+  formatRelativeTime,
+  getLocale,
+  t,
+} from '../../i18n/index.js';
 import { formatQuantity } from '../../ui/unitLabels.js';
 import { dayTime } from './model.js';
 
@@ -26,7 +31,10 @@ export const displayMetres = (value) => formatQuantity(value, 'm');
 /** The readout's words in the page's language; the model keeps them English. */
 export const READOUT_WORDS = Object.freeze({
   date: (day) => displayDay(day, LONG_DAY),
-  daysAgo: (delta) => formatRelativeTime(delta > 0 ? -delta : 0, 'day'),
+  daysAgo: (delta) => {
+    const text = formatRelativeTime(delta > 0 ? -delta : 0, 'day');
+    return getLocale() === 'zh-CN' ? text.replace(/(\d)(?=天)/g, '$1 ') : text;
+  },
   // "Sentinel-2" never breaks at its hyphen: a word joiner follows it
   // (JetBrains Mono has no U+2011 non-breaking hyphen).
   sensor: (sensor) =>
diff --git a/src/ui/cctvFrames.js b/src/ui/cctvFrames.js
index 7976d46c8..22f4f0dce 100644
--- a/src/ui/cctvFrames.js
+++ b/src/ui/cctvFrames.js
@@ -19,6 +19,7 @@ const SOURCE_KIND_LABELS = Object.freeze({
 });
 
 const SOURCE_STATUS_LABELS = Object.freeze({
+  ok: msg('OK'),
   degraded: msg('DEGRADED'),
   error: msg('ERROR'),
   unknown: msg('UNKNOWN'),
@@ -51,7 +52,7 @@ export function cctvSourceKindLabel(kind) {
     : key.toUpperCase();
 }
 
-/** "DEGRADED" / "ПЕРЕБОИ"; OK and unknown codes stay as uppercase codes. */
+/** "DEGRADED" / "ПЕРЕБОИ"; unknown codes stay as uppercase codes. */
 export function cctvSourceStatusLabel(status) {
   const key = String(status || 'unknown').toLowerCase();
   return SOURCE_STATUS_LABELS[key]
diff --git a/src/ui/cockpitContext.js b/src/ui/cockpitContext.js
index 57db349ee..852cc32a8 100644
--- a/src/ui/cockpitContext.js
+++ b/src/ui/cockpitContext.js
@@ -1,6 +1,6 @@
 /** Contact readouts and nearby-signal presentation for the Cockpit controller. */
 import * as Cesium from 'cesium';
-import { formatNumber, t, tn } from '../i18n/index.js';
+import { formatNumber, getLocale, t, tn } from '../i18n/index.js';
 import { unitLabel } from './unitLabels.js';
 import {
   bearingBetweenCoordinates,
@@ -15,7 +15,7 @@ const LOCALIZED_CONTEXT_SCOPE = Object.freeze({
   window: ({ label, radiusKm }) =>
     t('{label} · {radius} AIR/SEA WINDOW', {
       label,
-      radius: `${radiusKm === null ? '—' : formatNumber(radiusKm)}\u00a0${unitLabel('km').toUpperCase()}`,
+      radius: `${radiusKm === null ? '—' : formatNumber(radiusKm)}\u00a0${getLocale() === 'zh-CN' ? unitLabel('km') : unitLabel('km').toUpperCase()}`,
     }),
   installations: ({ scope, coverage }) =>
     t('{scope} · INSTALLATIONS {coverage}', { scope, coverage }),
diff --git a/src/ui/cockpitPresentation.js b/src/ui/cockpitPresentation.js
index f8930d4e0..8285b74b3 100644
--- a/src/ui/cockpitPresentation.js
+++ b/src/ui/cockpitPresentation.js
@@ -1,5 +1,5 @@
 /** Pure formatting and fixed presentation constants used by Cockpit components. */
-import { formatNumber, t, msg } from '../i18n/index.js';
+import { formatNumber, getLocale, t, msg } from '../i18n/index.js';
 import { formatQuantity } from './unitLabels.js';
 
 export const COCKPIT_HEADING_SLEW_DPS = 28;
@@ -145,10 +145,11 @@ export function formatCockpitCoordinate(value, positive, negative) {
  */
 export function formatCockpitDistance(distanceM) {
   const digits = distanceM < 10000 ? 1 : 0;
-  return formatQuantity(distanceM / 1000, 'km', {
+  const distance = formatQuantity(distanceM / 1000, 'km', {
     minimumFractionDigits: digits,
     maximumFractionDigits: digits,
-  }).toUpperCase();
+  });
+  return getLocale() === 'zh-CN' ? distance : distance.toUpperCase();
 }
 
 export function formatCockpitWindDirection(value) {
diff --git a/src/ui/radioPresentation.js b/src/ui/radioPresentation.js
index 94431fdec..54ee379e8 100644
--- a/src/ui/radioPresentation.js
+++ b/src/ui/radioPresentation.js
@@ -114,13 +114,14 @@ export function renderRadioState(state) {
         ...state.categories.map((category) => {
           const option = document.createElement('option');
           option.value = category.id;
-          option.textContent = `● ${category.label} (${category.count})`;
+          const label = t('{category} ({count})', {
+            category: category.label,
+            count: category.count,
+          });
+          option.textContent = `● ${label}`;
           option.dataset.radioColor = category.color;
           option.style.color = category.color;
-          option.setAttribute(
-            'aria-label',
-            `${category.label} (${category.count})`,
-          );
+          option.setAttribute('aria-label', label);
           return option;
         }),
       );
diff --git a/src/ui/styles/cjk.css b/src/ui/styles/cjk.css
index c44431520..9ecfa0ce3 100644
--- a/src/ui/styles/cjk.css
+++ b/src/ui/styles/cjk.css
@@ -27,3 +27,28 @@ html:lang(zh) .panel-layer-toggle {
 html:lang(zh) .pp-mode-btn {
   white-space: nowrap;
 }
+
+/* Keep unit symbols in their catalog case, including the cockpit readouts. */
+html:lang(zh) #intel-hud *,
+html:lang(zh) #cockpit-hud * {
+  text-transform: none;
+}
+
+/* Move short travel modes (步行 / 骑行) to the next line as whole words. */
+html:lang(zh) [data-layer-id='directions'] .data-toggle-meta {
+  word-break: keep-all;
+  overflow-wrap: break-word;
+}
+
+/* Leave room for the complete sensor name and resolution on two lines. */
+html:lang(zh) .recent-imagery-readout .ri-strip {
+  height: 131px;
+}
+html:lang(zh) .recent-imagery-readout .ri-card {
+  height: 123px;
+  grid-template-rows: 42px 13px 22px 11px 18px;
+}
+html:lang(zh) .recent-imagery-readout .ri-card-sensor {
+  white-space: normal;
+  text-overflow: clip;
+}