diff --git a/tests/unit/module/abbreviateNumber.test.js b/tests/unit/module/abbreviateNumber.test.js
new file mode 100644
index 0000000..f755c42
--- /dev/null
+++ b/tests/unit/module/abbreviateNumber.test.js
@@ -0,0 +1,46 @@
+import { describe, it, expect } from 'vitest';
+import abbreviateNumber from '@/module/abbreviateNumber.js';
+
+describe('abbreviateNumber', () => {
+  it('returns "0" for 0 seconds', () => {
+    expect(abbreviateNumber(0)).toBe('0');
+  });
+
+  it('returns seconds only when < 60', () => {
+    expect(abbreviateNumber(45).trim()).toBe('45s');
+  });
+
+  it('returns minutes and seconds', () => {
+    // 2m 30s = 150s
+    expect(abbreviateNumber(150).trim()).toBe('2m 30s');
+  });
+
+  it('returns hours, minutes, and seconds', () => {
+    // 1h 1m 1s = 3661s
+    expect(abbreviateNumber(3661).trim()).toBe('1h 1m 1s');
+  });
+
+  it('returns days, hours, minutes, and seconds', () => {
+    // 1d 2h 3m 4s = 93784s
+    expect(abbreviateNumber(93784).trim())
+      .toBe('1d 2h 3m 4s');
+  });
+
+  it('handles exact day boundary', () => {
+    // 1d = 86400s
+    expect(abbreviateNumber(86400).trim()).toBe('1d');
+  });
+
+  it('handles exact hour boundary', () => {
+    // 1h = 3600s
+    expect(abbreviateNumber(3600).trim()).toBe('1h');
+  });
+
+  it('handles string input by parsing as int', () => {
+    expect(abbreviateNumber('150').trim()).toBe('2m 30s');
+  });
+
+  it('handles NaN input', () => {
+    expect(abbreviateNumber('abc').trim()).toBe('');
+  });
+});
diff --git a/tests/unit/module/numberLabel.test.js b/tests/unit/module/numberLabel.test.js
new file mode 100644
index 0000000..542e02d
--- /dev/null
+++ b/tests/unit/module/numberLabel.test.js
@@ -0,0 +1,26 @@
+import { describe, it, expect } from 'vitest';
+import numberLabel from '@/module/numberLabel.js';
+
+describe('numberLabel', () => {
+  it('formats small numbers without commas', () => {
+    expect(numberLabel(1)).toBe('1');
+    expect(numberLabel(999)).toBe('999');
+  });
+
+  it('formats thousands with commas', () => {
+    expect(numberLabel(1000)).toBe('1,000');
+    expect(numberLabel(12345)).toBe('12,345');
+  });
+
+  it('formats millions with commas', () => {
+    expect(numberLabel(1234567)).toBe('1,234,567');
+  });
+
+  it('preserves decimal places', () => {
+    expect(numberLabel(1234.56)).toBe('1,234.56');
+  });
+
+  it('handles zero', () => {
+    expect(numberLabel(0)).toBe('0');
+  });
+});
diff --git a/tests/unit/module/setChartData.test.js b/tests/unit/module/setChartData.test.js
new file mode 100644
index 0000000..4da9e0b
--- /dev/null
+++ b/tests/unit/module/setChartData.test.js
@@ -0,0 +1,130 @@
+import { describe, it, expect } from 'vitest';
+import {
+  setLineChartData,
+  setBarChartData,
+  timeRange,
+  yTimeRange,
+  getXIndex,
+  formatTime,
+  formatMaxTwo,
+} from '@/module/setChartData.js';
+
+describe('timeRange', () => {
+  it('splits time into equal parts', () => {
+    const result = timeRange(0, 100, 3);
+    expect(result).toEqual([0, 50, 100]);
+  });
+
+  it('rounds values to integers', () => {
+    const result = timeRange(0, 10, 4);
+    // 0, 3.33, 6.67, 10 -> rounded
+    expect(result).toEqual([0, 3, 7, 10]);
+  });
+});
+
+describe('getXIndex', () => {
+  it('finds exact match index', () => {
+    expect(getXIndex([10, 20, 30], 20)).toBe(1);
+  });
+
+  it('finds closest value index', () => {
+    expect(getXIndex([10, 20, 30], 22)).toBe(1);
+  });
+
+  it('returns last matching index for equal distances', () => {
+    // 15 is equidistant from 10 and 20, <= means last wins
+    expect(getXIndex([10, 20, 30], 15)).toBe(1);
+  });
+});
+
+describe('formatTime', () => {
+  it('formats seconds only', () => {
+    expect(formatTime(45)).toBe('45s');
+  });
+
+  it('formats minutes and seconds', () => {
+    expect(formatTime(125)).toBe('2m5s');
+  });
+
+  it('formats hours, minutes, seconds', () => {
+    expect(formatTime(3661)).toBe('1h1m1s');
+  });
+
+  it('formats days', () => {
+    expect(formatTime(90061)).toBe('1d1h1m1s');
+  });
+
+  it('returns null for NaN', () => {
+    expect(formatTime('abc')).toBeNull();
+  });
+
+  it('handles zero seconds', () => {
+    expect(formatTime(0)).toBe('0s');
+  });
+});
+
+describe('formatMaxTwo', () => {
+  it('keeps only top two units', () => {
+    expect(formatMaxTwo(['1d2h3m4s'])).toEqual(['1d 2h']);
+  });
+
+  it('keeps single unit as-is', () => {
+    expect(formatMaxTwo(['45s'])).toEqual(['45s']);
+  });
+
+  it('handles two units', () => {
+    expect(formatMaxTwo(['3m20s'])).toEqual(['3m 20s']);
+  });
+
+  it('processes multiple items', () => {
+    expect(formatMaxTwo(['1h30m10s', '45s']))
+      .toEqual(['1h 30m', '45s']);
+  });
+});
+
+describe('setLineChartData', () => {
+  it('prepends min and appends max to data', () => {
+    const baseData = [
+      { x: 1, y: 10 }, { x: 2, y: 20 },
+      { x: 3, y: 30 }, { x: 4, y: 40 },
+      { x: 5, y: 50 }, { x: 6, y: 60 },
+      { x: 7, y: 70 }, { x: 8, y: 80 },
+      { x: 9, y: 90 }, { x: 10, y: 100 },
+    ];
+    const result = setLineChartData(
+      baseData, 'xMax', 'xMin', false, 200, 0
+    );
+    // Should have 12 elements (10 original + 2 boundary)
+    expect(result).toHaveLength(12);
+    expect(result[0].x).toBe('xMin');
+    expect(result[11].x).toBe('xMax');
+  });
+
+  it('clamps percent values between 0 and 1', () => {
+    const baseData = [
+      { x: 1, y: 0.1 }, { x: 2, y: 0.2 },
+      { x: 3, y: 0.3 }, { x: 4, y: 0.4 },
+      { x: 5, y: 0.5 }, { x: 6, y: 0.6 },
+      { x: 7, y: 0.7 }, { x: 8, y: 0.8 },
+      { x: 9, y: 0.9 }, { x: 10, y: 0.95 },
+    ];
+    const result = setLineChartData(
+      baseData, 'xMax', 'xMin', true, 1, 0
+    );
+    expect(result[0].y).toBeGreaterThanOrEqual(0);
+    expect(result[0].y).toBeLessThanOrEqual(1);
+    expect(result[11].y).toBeGreaterThanOrEqual(0);
+    expect(result[11].y).toBeLessThanOrEqual(1);
+  });
+});
+
+describe('setBarChartData', () => {
+  it('converts x values to formatted date strings', () => {
+    const baseData = [
+      { x: '2023-01-15T12:00:00', y: 100 },
+    ];
+    const result = setBarChartData(baseData);
+    expect(result[0].y).toBe(100);
+    expect(result[0].x).toMatch(/2023\/1\/15/);
+  });
+});
diff --git a/tests/unit/module/shortScaleNumber.test.js b/tests/unit/module/shortScaleNumber.test.js
new file mode 100644
index 0000000..3ee8093
--- /dev/null
+++ b/tests/unit/module/shortScaleNumber.test.js
@@ -0,0 +1,36 @@
+import { describe, it, expect } from 'vitest';
+import shortScaleNumber from '@/module/shortScaleNumber.js';
+
+describe('shortScaleNumber', () => {
+  it('returns small numbers without abbreviation', () => {
+    expect(shortScaleNumber(1).trim()).toBe('1');
+    expect(shortScaleNumber(999).trim()).toBe('999');
+  });
+
+  it('abbreviates thousands as k', () => {
+    expect(shortScaleNumber(1000).trim()).toBe('1k');
+    expect(shortScaleNumber(1500).trim()).toBe('1.5k');
+  });
+
+  it('abbreviates millions as m', () => {
+    expect(shortScaleNumber(1000000).trim()).toBe('1m');
+  });
+
+  it('abbreviates billions as b', () => {
+    expect(shortScaleNumber(1000000000).trim()).toBe('1b');
+  });
+
+  it('abbreviates trillions as t', () => {
+    expect(shortScaleNumber(1000000000000).trim())
+      .toBe('1t');
+  });
+
+  it('rounds up using Math.ceil', () => {
+    // 1234 -> 1.234k -> ceil(12.34)/10 = 1.3k
+    expect(shortScaleNumber(1234).trim()).toBe('1.3k');
+  });
+
+  it('handles zero', () => {
+    expect(shortScaleNumber(0).trim()).toBe('0');
+  });
+});
diff --git a/tests/unit/module/sortNumEngZhtw.test.js b/tests/unit/module/sortNumEngZhtw.test.js
new file mode 100644
index 0000000..3a3345c
--- /dev/null
+++ b/tests/unit/module/sortNumEngZhtw.test.js
@@ -0,0 +1,52 @@
+import { describe, it, expect } from 'vitest';
+import {
+  sortNumEngZhtw,
+  sortNumEngZhtwForFilter,
+} from '@/module/sortNumEngZhtw.js';
+
+describe('sortNumEngZhtw', () => {
+  it('sorts numbers in ascending order', () => {
+    expect(sortNumEngZhtw(['3', '1', '2']))
+      .toEqual(['1', '2', '3']);
+  });
+
+  it('places numbers before strings', () => {
+    expect(sortNumEngZhtw(['b', '1', 'a']))
+      .toEqual(['1', 'a', 'b']);
+  });
+
+  it('sorts English strings alphabetically', () => {
+    expect(sortNumEngZhtw(['cherry', 'apple', 'banana']))
+      .toEqual(['apple', 'banana', 'cherry']);
+  });
+
+  it('sorts mixed numbers and strings', () => {
+    const input = ['banana', '10', 'apple', '2'];
+    const result = sortNumEngZhtw(input);
+    expect(result).toEqual(['2', '10', 'apple', 'banana']);
+  });
+});
+
+describe('sortNumEngZhtwForFilter', () => {
+  it('returns negative when a < b (numbers)', () => {
+    expect(sortNumEngZhtwForFilter('1', '2'))
+      .toBeLessThan(0);
+  });
+
+  it('returns positive when a > b (numbers)', () => {
+    expect(sortNumEngZhtwForFilter('10', '2'))
+      .toBeGreaterThan(0);
+  });
+
+  it('places numbers before strings', () => {
+    expect(sortNumEngZhtwForFilter('1', 'a'))
+      .toBeLessThan(0);
+    expect(sortNumEngZhtwForFilter('a', '1'))
+      .toBeGreaterThan(0);
+  });
+
+  it('compares strings using locale', () => {
+    expect(sortNumEngZhtwForFilter('a', 'b'))
+      .toBeLessThan(0);
+  });
+});
diff --git a/tests/unit/module/timeLabel.test.js b/tests/unit/module/timeLabel.test.js
new file mode 100644
index 0000000..ca70263
--- /dev/null
+++ b/tests/unit/module/timeLabel.test.js
@@ -0,0 +1,147 @@
+import { describe, it, expect } from 'vitest';
+import {
+  getTimeLabel,
+  simpleTimeLabel,
+  followTimeLabel,
+  getStepSizeOfYTicks,
+  getYTicksByIndex,
+  setTimeStringFormatBaseOnTimeDifference,
+  mapTimestampToAxisTicksByFormat,
+} from '@/module/timeLabel.js';
+
+describe('getTimeLabel', () => {
+  it('returns days for >= 86400 seconds', () => {
+    expect(getTimeLabel(86400)).toBe('1 days');
+    expect(getTimeLabel(172800)).toBe('2 days');
+  });
+
+  it('returns hours for >= 3600 seconds', () => {
+    expect(getTimeLabel(3600)).toBe('1 hrs');
+    expect(getTimeLabel(7200)).toBe('2 hrs');
+  });
+
+  it('returns minutes for >= 60 seconds', () => {
+    expect(getTimeLabel(60)).toBe('1 mins');
+    expect(getTimeLabel(120)).toBe('2 mins');
+  });
+
+  it('returns seconds for < 60', () => {
+    expect(getTimeLabel(30)).toBe('30 sec');
+  });
+
+  it('returns 0 sec for zero', () => {
+    expect(getTimeLabel(0)).toBe('0 sec');
+  });
+
+  it('respects fixedNumber parameter', () => {
+    expect(getTimeLabel(5400, 1)).toBe('1.5 hrs');
+  });
+});
+
+describe('simpleTimeLabel', () => {
+  it('returns days with d suffix', () => {
+    expect(simpleTimeLabel(86400)).toBe('1d');
+  });
+
+  it('returns seconds with s suffix for small values', () => {
+    expect(simpleTimeLabel(30)).toBe('30s');
+  });
+
+  it('returns 0s for zero', () => {
+    expect(simpleTimeLabel(0)).toBe('0s');
+  });
+});
+
+describe('followTimeLabel', () => {
+  it('uses day unit when max > 1 day', () => {
+    // max = 100000 (> 86400), second = 86400 => 1d
+    expect(followTimeLabel(86400, 100000)).toBe('1d');
+  });
+
+  it('uses hour unit when max > 1 hour', () => {
+    // max = 7200 (> 3600), second = 3600 => 1h
+    expect(followTimeLabel(3600, 7200)).toBe('1h');
+  });
+
+  it('uses minute unit when max > 1 minute', () => {
+    // max = 120 (> 60), second = 60 => 1m
+    expect(followTimeLabel(60, 120)).toBe('1m');
+  });
+
+  it('uses second unit when max <= 60', () => {
+    expect(followTimeLabel(30, 50)).toBe('30s');
+  });
+
+  it('returns 0 without decimals when value is 0', () => {
+    expect(followTimeLabel(0, 7200, 2)).toBe('0h');
+  });
+});
+
+describe('getStepSizeOfYTicks', () => {
+  it('returns object with resultStepSize and unitToUse', () => {
+    const result = getStepSizeOfYTicks(7200, 5);
+    expect(result).toHaveProperty('resultStepSize');
+    expect(result).toHaveProperty('unitToUse');
+    expect(result.unitToUse).toBe('h');
+  });
+
+  it('uses day unit for large values', () => {
+    const result = getStepSizeOfYTicks(200000, 5);
+    expect(result.unitToUse).toBe('d');
+  });
+
+  it('uses second unit for small values', () => {
+    const result = getStepSizeOfYTicks(30, 5);
+    expect(result.unitToUse).toBe('s');
+  });
+});
+
+describe('getYTicksByIndex', () => {
+  it('formats tick label with unit', () => {
+    expect(getYTicksByIndex(2, 3, 'h')).toBe('6h');
+  });
+
+  it('truncates to 1 decimal place', () => {
+    expect(getYTicksByIndex(1.5, 1, 'h')).toBe('1.5h');
+  });
+});
+
+describe('setTimeStringFormatBaseOnTimeDifference', () => {
+  it('returns seconds format for < 60s difference', () => {
+    expect(setTimeStringFormatBaseOnTimeDifference(0, 30))
+      .toBe('HH:mm:ss');
+  });
+
+  it('returns minute format for < 3600s difference', () => {
+    expect(setTimeStringFormatBaseOnTimeDifference(0, 1800))
+      .toBe('MM/DD HH:mm');
+  });
+
+  it('returns hour format for < 86400s difference', () => {
+    expect(setTimeStringFormatBaseOnTimeDifference(0, 43200))
+      .toBe('MM/DD HH:mm');
+  });
+
+  it('returns day format for < 30 days difference', () => {
+    expect(setTimeStringFormatBaseOnTimeDifference(0, 864000))
+      .toBe('YYYY/MM/DD');
+  });
+
+  it('returns month format for >= 30 days difference', () => {
+    expect(setTimeStringFormatBaseOnTimeDifference(0, 5000000))
+      .toBe('YYYY/MM/DD');
+  });
+});
+
+describe('mapTimestampToAxisTicksByFormat', () => {
+  it('formats timestamps with given format', () => {
+    const ts = [new Date('2023-01-15').getTime()];
+    const result = mapTimestampToAxisTicksByFormat(ts, 'YYYY/MM/DD');
+    expect(result[0]).toBe('2023/01/15');
+  });
+
+  it('returns undefined for falsy input', () => {
+    expect(mapTimestampToAxisTicksByFormat(null, 'YYYY'))
+      .toBeUndefined();
+  });
+});
diff --git a/tests/unit/utils/cookieUtil.test.js b/tests/unit/utils/cookieUtil.test.js
new file mode 100644
index 0000000..4642f3a
--- /dev/null
+++ b/tests/unit/utils/cookieUtil.test.js
@@ -0,0 +1,72 @@
+import { describe, it, expect, beforeEach } from 'vitest';
+import {
+  getCookie,
+  setCookie,
+  setCookieWithoutExpiration,
+  deleteCookie,
+} from '@/utils/cookieUtil.js';
+
+describe('cookieUtil', () => {
+  beforeEach(() => {
+    // Clear all cookies before each test
+    document.cookie.split(';').forEach((c) => {
+      const name = c.split('=')[0].trim();
+      if (name) {
+        document.cookie =
+          name + '=; Max-Age=-99999999; path=/';
+      }
+    });
+  });
+
+  describe('getCookie', () => {
+    it('returns null when cookie does not exist', () => {
+      expect(getCookie('nonexistent')).toBeNull();
+    });
+
+    it('returns value of an existing cookie', () => {
+      document.cookie = 'testKey=testValue';
+      expect(getCookie('testKey')).toBe('testValue');
+    });
+
+    it('returns correct value when multiple cookies exist',
+      () => {
+        document.cookie = 'first=aaa';
+        document.cookie = 'second=bbb';
+        document.cookie = 'third=ccc';
+        expect(getCookie('second')).toBe('bbb');
+      });
+
+    it('does not match partial cookie names', () => {
+      document.cookie = 'testKey=value';
+      expect(getCookie('test')).toBeNull();
+    });
+  });
+
+  describe('setCookie', () => {
+    it('sets a cookie with default 1-day expiration', () => {
+      setCookie('myKey', 'myValue');
+      expect(getCookie('myKey')).toBe('myValue');
+    });
+
+    it('sets a cookie with empty value', () => {
+      setCookie('emptyKey', '');
+      expect(getCookie('emptyKey')).toBe('');
+    });
+  });
+
+  describe('setCookieWithoutExpiration', () => {
+    it('sets a session cookie', () => {
+      setCookieWithoutExpiration('sessionKey', 'sessionVal');
+      expect(getCookie('sessionKey')).toBe('sessionVal');
+    });
+  });
+
+  describe('deleteCookie', () => {
+    it('removes an existing cookie', () => {
+      setCookie('toDelete', 'value');
+      expect(getCookie('toDelete')).toBe('value');
+      deleteCookie('toDelete');
+      expect(getCookie('toDelete')).toBeNull();
+    });
+  });
+});
diff --git a/tests/unit/utils/pageUtils.test.js b/tests/unit/utils/pageUtils.test.js
new file mode 100644
index 0000000..f017ac4
--- /dev/null
+++ b/tests/unit/utils/pageUtils.test.js
@@ -0,0 +1,54 @@
+import { describe, it, expect } from 'vitest';
+import {
+  mapPageNameToCapitalUnifiedName,
+} from '@/utils/pageUtils.js';
+
+describe('pageUtils', () => {
+  describe('mapPageNameToCapitalUnifiedName', () => {
+    it('converts CheckMap to MAP', () => {
+      expect(mapPageNameToCapitalUnifiedName('CheckMap'))
+        .toBe('MAP');
+    });
+
+    it('converts CheckConformance to CONFORMANCE', () => {
+      expect(
+        mapPageNameToCapitalUnifiedName('CheckConformance')
+      ).toBe('CONFORMANCE');
+    });
+
+    it('converts CheckPerformance to PERFORMANCE', () => {
+      expect(
+        mapPageNameToCapitalUnifiedName('CheckPerformance')
+      ).toBe('PERFORMANCE');
+    });
+
+    it('converts CompareDashboard to DASHBOARD', () => {
+      expect(
+        mapPageNameToCapitalUnifiedName('CompareDashboard')
+      ).toBe('DASHBOARD');
+    });
+
+    it('converts other names to uppercase', () => {
+      expect(mapPageNameToCapitalUnifiedName('files'))
+        .toBe('FILES');
+      expect(mapPageNameToCapitalUnifiedName('Map'))
+        .toBe('MAP');
+    });
+
+    it('handles case-insensitive input', () => {
+      expect(mapPageNameToCapitalUnifiedName('checkmap'))
+        .toBe('MAP');
+      expect(mapPageNameToCapitalUnifiedName('CHECKMAP'))
+        .toBe('MAP');
+    });
+
+    it('returns undefined for falsy input', () => {
+      expect(mapPageNameToCapitalUnifiedName(undefined))
+        .toBeUndefined();
+      expect(mapPageNameToCapitalUnifiedName(null))
+        .toBeUndefined();
+      expect(mapPageNameToCapitalUnifiedName(''))
+        .toBeUndefined();
+    });
+  });
+});