diff --git a/src/pages/Landing.tsx b/src/pages/Landing.tsx
index 265bd0c..04f27d6 100644
--- a/src/pages/Landing.tsx
+++ b/src/pages/Landing.tsx
@@ -9,7 +9,7 @@ import { Clock, Filter, Grid2X2 } from 'lucide-react';
 const CATEGORIES = [
   { name: 'Generators', slugs: ['uuid', 'nanoid', 'password', 'objectid', 'qr'] },
   { name: 'Encoders & Decoders', slugs: ['base64', 'url', 'jwt-decode'] },
-  { name: 'Converters & Formatters', slugs: ['json', 'color', 'json-to-ts'] },
+  { name: 'Converters & Formatters', slugs: ['json', 'color', 'json-to-ts', 'case-converter'] },
   { name: 'API & Networking', slugs: ['api-tester'] },
   { name: 'Security & Crypto', slugs: ['hash', 'jwt'] },
   { name: 'Utilities', slugs: ['timestamp', 'regex', 'markdown'] }
diff --git a/src/tools/case-converter/CaseConverterTool.tsx b/src/tools/case-converter/CaseConverterTool.tsx
new file mode 100644
index 0000000..e51800c
--- /dev/null
+++ b/src/tools/case-converter/CaseConverterTool.tsx
@@ -0,0 +1,300 @@
+import { useState, useMemo, useEffect } from 'react';
+import { ToolLayout } from '../../components/ToolLayout';
+import { Button } from '../../components/ui/Button';
+import { CopyButton } from '../../components/ui/CopyButton';
+import { useUrlState } from '../../hooks/useUrlState';
+import {
+  convertAllCases,
+  detectCasing,
+  extractWords,
+  toCamelCase,
+  toPascalCase,
+  toSnakeCase,
+  toConstantCase,
+  toKebabCase,
+  toSlug,
+  toTitleCase,
+  toSentenceCase,
+  toDotCase,
+  toPathCase,
+  type CaseResult,
+} from './caseConverter';
+
+const SAMPLES = [
+  'user_profile_data',
+  'APIResponseHandler',
+  'fast-furious-tokyo-drift',
+  'Café & Restaurant',
+  'document.body.style',
+];
+
+const BATCH_TARGETS = [
+  { label: 'camelCase', fn: (w: string[]) => toCamelCase(w) },
+  { label: 'PascalCase', fn: (w: string[]) => toPascalCase(w) },
+  { label: 'snake_case', fn: (w: string[]) => toSnakeCase(w) },
+  { label: 'CONSTANT_CASE', fn: (w: string[]) => toConstantCase(w) },
+  { label: 'kebab-case', fn: (w: string[]) => toKebabCase(w) },
+  { label: 'URL Slug', fn: (_w: string[], raw: string) => toSlug(raw) },
+  { label: 'Title Case', fn: (w: string[]) => toTitleCase(w) },
+  { label: 'Sentence case', fn: (w: string[]) => toSentenceCase(w) },
+  { label: 'dot.case', fn: (w: string[]) => toDotCase(w) },
+  { label: 'path/case', fn: (w: string[]) => toPathCase(w) },
+  { label: 'lowercase', fn: (_w: string[], raw: string) => raw.toLowerCase() },
+  { label: 'UPPERCASE', fn: (_w: string[], raw: string) => raw.toUpperCase() },
+];
+
+export default function CaseConverterTool() {
+  const [urlText, setUrlText] = useUrlState('t', 'hello_world_example', String, String);
+  const [text, setTextInternal] = useState(urlText);
+  const [isBatch, setIsBatch] = useState(false);
+  const [batchTarget, setBatchTarget] = useState('camelCase');
+
+  const setText = (val: string) => {
+    setTextInternal(val);
+    setUrlText(val);
+  };
+
+  useEffect(() => {
+    setTextInternal(urlText);
+  }, [urlText]);
+
+  const detected = useMemo(() => detectCasing(text), [text]);
+  const results: CaseResult[] = useMemo(() => convertAllCases(text), [text]);
+
+  const batchOutput = useMemo(() => {
+    if (!text) return '';
+    const targetObj = BATCH_TARGETS.find((t) => t.label === batchTarget) || BATCH_TARGETS[0];
+    return text
+      .split('\n')
+      .map((line) => {
+        const words = extractWords(line);
+        return targetObj.fn(words, line);
+      })
+      .join('\n');
+  }, [text, batchTarget]);
+
+  return (
+    <ToolLayout>
+      <div style={{ display: 'flex', flexDirection: 'column', gap: 20 }}>
+        {/* Controls row */}
+        <div style={{ display: 'flex', justifyContent: 'space-between', alignItems: 'center', flexWrap: 'wrap', gap: 10 }}>
+          {/* Quick samples */}
+          <div style={{ display: 'flex', alignItems: 'center', gap: 6, flexWrap: 'wrap' }}>
+            <span style={{ fontSize: 12, fontWeight: 600, color: 'var(--ink-mute)' }}>Examples:</span>
+            {SAMPLES.map((s) => (
+              <button
+                key={s}
+                type="button"
+                onClick={() => setText(s)}
+                style={{
+                  padding: '4px 8px',
+                  borderRadius: 6,
+                  background: 'var(--surface-nav-item)',
+                  border: '1px solid var(--line)',
+                  fontSize: 12,
+                  fontFamily: 'var(--font-mono)',
+                  color: 'var(--ink-soft)',
+                  cursor: 'pointer',
+                }}
+              >
+                {s}
+              </button>
+            ))}
+          </div>
+
+          {/* Mode Switcher */}
+          <div style={{ display: 'flex', gap: 6 }}>
+            <button
+              type="button"
+              onClick={() => setIsBatch(false)}
+              style={{
+                padding: '6px 12px',
+                borderRadius: 8,
+                fontSize: 12,
+                fontWeight: 600,
+                background: !isBatch ? 'rgba(139, 92, 246, 0.18)' : 'var(--surface-nav-item)',
+                border: `1px solid ${!isBatch ? 'rgba(139, 92, 246, 0.4)' : 'var(--line)'}`,
+                color: 'var(--ink)',
+                cursor: 'pointer',
+              }}
+            >
+              All Formats
+            </button>
+            <button
+              type="button"
+              onClick={() => setIsBatch(true)}
+              style={{
+                padding: '6px 12px',
+                borderRadius: 8,
+                fontSize: 12,
+                fontWeight: 600,
+                background: isBatch ? 'rgba(139, 92, 246, 0.18)' : 'var(--surface-nav-item)',
+                border: `1px solid ${isBatch ? 'rgba(139, 92, 246, 0.4)' : 'var(--line)'}`,
+                color: 'var(--ink)',
+                cursor: 'pointer',
+              }}
+            >
+              Batch Multi-Line
+            </button>
+          </div>
+        </div>
+
+        {/* Input Textarea */}
+        <div style={{ position: 'relative' }}>
+          <textarea
+            value={text}
+            onChange={(e) => setText(e.target.value)}
+            placeholder="Type or paste text to convert..."
+            rows={isBatch ? 5 : 3}
+            aria-label="Text input to convert"
+            style={{
+              width: '100%',
+              padding: '12px 14px',
+              borderRadius: 12,
+              border: '1px solid var(--line)',
+              background: 'var(--surface-input)',
+              fontSize: 14,
+              fontFamily: 'var(--font-mono)',
+              color: 'var(--ink)',
+              outline: 'none',
+              resize: 'vertical',
+            }}
+          />
+
+          <div
+            style={{
+              display: 'flex',
+              alignItems: 'center',
+              justifyContent: 'space-between',
+              marginTop: 6,
+              fontSize: 11,
+              color: 'var(--ink-mute)',
+            }}
+          >
+            <span>
+              Detected: <strong style={{ color: 'var(--accent)' }}>{detected}</strong> · {text.length} chars
+            </span>
+            {text && (
+              <button
+                type="button"
+                onClick={() => setText('')}
+                style={{
+                  background: 'transparent',
+                  border: 'none',
+                  color: 'var(--ink-mute)',
+                  cursor: 'pointer',
+                  fontSize: 11,
+                  textDecoration: 'underline',
+                }}
+              >
+                Clear
+              </button>
+            )}
+          </div>
+        </div>
+
+        {/* Single Mode: All Formats Grid */}
+        {!isBatch ? (
+          <div
+            style={{
+              display: 'grid',
+              gridTemplateColumns: 'repeat(auto-fit, minmax(280px, 1fr))',
+              gap: 14,
+            }}
+          >
+            {results.map((res) => (
+              <div
+                key={res.id}
+                style={{
+                  padding: '14px 16px',
+                  borderRadius: 14,
+                  background: 'var(--surface-nav-item)',
+                  border: '1px solid var(--glass-border)',
+                  display: 'flex',
+                  flexDirection: 'column',
+                  gap: 8,
+                }}
+              >
+                <div style={{ display: 'flex', justifyContent: 'space-between', alignItems: 'center' }}>
+                  <span style={{ fontSize: 12, fontWeight: 600, color: 'var(--ink-mute)' }}>{res.name}</span>
+                  <CopyButton value={res.value} label="Copy" size="sm" />
+                </div>
+                <div
+                  style={{
+                    fontFamily: 'var(--font-mono)',
+                    fontSize: 14,
+                    fontWeight: 600,
+                    color: 'var(--ink)',
+                    wordBreak: 'break-all',
+                    minHeight: 22,
+                  }}
+                >
+                  {res.value || <span style={{ color: 'var(--ink-mute)', fontWeight: 400 }}>—</span>}
+                </div>
+              </div>
+            ))}
+          </div>
+        ) : (
+          /* Batch Multi-Line Mode */
+          <div style={{ display: 'flex', flexDirection: 'column', gap: 14 }}>
+            <div style={{ display: 'flex', alignItems: 'center', gap: 10, flexWrap: 'wrap' }}>
+              <span style={{ fontSize: 13, fontWeight: 600, color: 'var(--ink)' }}>Convert all lines to:</span>
+              <div style={{ display: 'flex', flexWrap: 'wrap', gap: 6 }}>
+                {BATCH_TARGETS.map((t) => (
+                  <button
+                    key={t.label}
+                    type="button"
+                    onClick={() => setBatchTarget(t.label)}
+                    style={{
+                      padding: '4px 10px',
+                      borderRadius: 6,
+                      fontSize: 12,
+                      fontWeight: 500,
+                      background: batchTarget === t.label ? 'rgba(139, 92, 246, 0.2)' : 'var(--surface-button-off)',
+                      border: `1px solid ${batchTarget === t.label ? 'rgba(139, 92, 246, 0.4)' : 'var(--line)'}`,
+                      color: 'var(--ink)',
+                      cursor: 'pointer',
+                    }}
+                  >
+                    {t.label}
+                  </button>
+                ))}
+              </div>
+            </div>
+
+            <div style={{ position: 'relative' }}>
+              <textarea
+                readOnly
+                value={batchOutput}
+                placeholder="Converted multi-line output will appear here..."
+                rows={6}
+                aria-label="Batch converted output"
+                style={{
+                  width: '100%',
+                  padding: '12px 14px',
+                  borderRadius: 12,
+                  border: '1px solid var(--line)',
+                  background: 'var(--surface-input)',
+                  fontSize: 14,
+                  fontFamily: 'var(--font-mono)',
+                  color: 'var(--accent)',
+                  outline: 'none',
+                }}
+              />
+              <div style={{ position: 'absolute', top: 12, right: 12 }}>
+                <CopyButton value={batchOutput} label="Copy Output" size="sm" />
+              </div>
+            </div>
+          </div>
+        )}
+
+        {/* Action bar */}
+        <div style={{ display: 'flex', gap: 10 }}>
+          <Button onClick={() => setText('hello_world_example')} variant="soft">
+            Reset Sample
+          </Button>
+        </div>
+      </div>
+    </ToolLayout>
+  );
+}
diff --git a/src/tools/case-converter/caseConverter.test.ts b/src/tools/case-converter/caseConverter.test.ts
new file mode 100644
index 0000000..b9da70b
--- /dev/null
+++ b/src/tools/case-converter/caseConverter.test.ts
@@ -0,0 +1,149 @@
+import { describe, it, expect } from 'vitest';
+import {
+  extractWords,
+  toCamelCase,
+  toPascalCase,
+  toSnakeCase,
+  toConstantCase,
+  toKebabCase,
+  toTitleCase,
+  toSentenceCase,
+  toDotCase,
+  toPathCase,
+  toSlug,
+  detectCasing,
+  convertAllCases,
+} from './caseConverter';
+
+describe('caseConverter logic', () => {
+  it('extracts words from diverse input casing conventions', () => {
+    expect(extractWords('helloWorld')).toEqual(['hello', 'World']);
+    expect(extractWords('HelloWorldTest')).toEqual(['Hello', 'World', 'Test']);
+    expect(extractWords('hello_world_test')).toEqual(['hello', 'world', 'test']);
+    expect(extractWords('HELLO_WORLD_TEST')).toEqual(['HELLO', 'WORLD', 'TEST']);
+    expect(extractWords('hello-world-test')).toEqual(['hello', 'world', 'test']);
+    expect(extractWords('hello.world.test')).toEqual(['hello', 'world', 'test']);
+    expect(extractWords('hello/world/test')).toEqual(['hello', 'world', 'test']);
+    expect(extractWords('XMLHttpRequest')).toEqual(['XML', 'Http', 'Request']);
+  });
+
+  it('handles empty and whitespace input', () => {
+    expect(extractWords('')).toEqual([]);
+    expect(extractWords('   ')).toEqual([]);
+    expect(toCamelCase([])).toBe('');
+    expect(toSentenceCase([])).toBe('');
+    expect(toSlug('')).toBe('');
+  });
+
+  it('converts to camelCase', () => {
+    expect(toCamelCase(['hello', 'world'])).toBe('helloWorld');
+    expect(toCamelCase(['user', 'profile', 'data'])).toBe('userProfileData');
+  });
+
+  it('converts to PascalCase', () => {
+    expect(toPascalCase(['hello', 'world'])).toBe('HelloWorld');
+  });
+
+  it('converts to snake_case and CONSTANT_CASE', () => {
+    expect(toSnakeCase(['Hello', 'World'])).toBe('hello_world');
+    expect(toConstantCase(['Hello', 'World'])).toBe('HELLO_WORLD');
+  });
+
+  it('converts to kebab-case, dot.case, and path/case', () => {
+    expect(toKebabCase(['hello', 'world'])).toBe('hello-world');
+    expect(toDotCase(['hello', 'world'])).toBe('hello.world');
+    expect(toPathCase(['hello', 'world'])).toBe('hello/world');
+  });
+
+  it('converts to Title Case and Sentence case', () => {
+    expect(toTitleCase(['hello', 'world', 'again'])).toBe('Hello World Again');
+    expect(toSentenceCase(['hello', 'world', 'again'])).toBe('Hello world again');
+  });
+
+  it('generates clean URL slugs stripping unicode diacritics', () => {
+    expect(toSlug('Café & Restaurant — 2026!')).toBe('cafe-restaurant-2026');
+    expect(toSlug('Crème Brûlée at Noël')).toBe('creme-brulee-at-noel');
+    expect(toSlug('Niño Español')).toBe('nino-espanol');
+    expect(toSlug('---Hello   World---')).toBe('hello-world');
+  });
+
+  it('detects common casing formats accurately', () => {
+    expect(detectCasing('camelCase')).toBe('camelCase');
+    expect(detectCasing('PascalCase')).toBe('PascalCase');
+    expect(detectCasing('snake_case')).toBe('snake_case');
+    expect(detectCasing('CONSTANT_CASE')).toBe('CONSTANT_CASE');
+    expect(detectCasing('kebab-case')).toBe('kebab-case');
+    expect(detectCasing('dot.case')).toBe('dot.case');
+    expect(detectCasing('path/case')).toBe('path/case');
+    expect(detectCasing('lowercase')).toBe('lowercase');
+    expect(detectCasing('UPPERCASE')).toBe('UPPERCASE');
+    expect(detectCasing('Camel')).toBe('Capitalized');
+    expect(detectCasing('Café')).toBe('Capitalized');
+    expect(detectCasing('café')).toBe('lowercase');
+    expect(detectCasing('CAFÉ')).toBe('UPPERCASE');
+    expect(detectCasing('Plain english text here')).toBe('Natural text');
+    expect(detectCasing('')).toBe('Unknown');
+  });
+
+  it('convertAllCases returns all 12 formats', () => {
+    const results = convertAllCases('user_account_setting');
+    expect(results).toHaveLength(12);
+
+    const map = Object.fromEntries(results.map((r) => [r.id, r.value]));
+    expect(map.camel).toBe('userAccountSetting');
+    expect(map.pascal).toBe('UserAccountSetting');
+    expect(map.snake).toBe('user_account_setting');
+    expect(map.constant).toBe('USER_ACCOUNT_SETTING');
+    expect(map.kebab).toBe('user-account-setting');
+    expect(map.slug).toBe('user-account-setting');
+    expect(map.title).toBe('User Account Setting');
+    expect(map.sentence).toBe('User account setting');
+    expect(map.dot).toBe('user.account.setting');
+    expect(map.path).toBe('user/account/setting');
+  });
+
+  it('preserves accented and international letters across case conversions', () => {
+    const cafeWords = extractWords('caféLatte');
+    expect(cafeWords).toEqual(['café', 'Latte']);
+    expect(toSnakeCase(cafeWords)).toBe('café_latte');
+    expect(toPascalCase(cafeWords)).toBe('CaféLatte');
+    expect(toConstantCase(cafeWords)).toBe('CAFÉ_LATTE');
+    expect(toKebabCase(cafeWords)).toBe('café-latte');
+    expect(toTitleCase(cafeWords)).toBe('Café Latte');
+    expect(toSentenceCase(cafeWords)).toBe('Café latte');
+    expect(toDotCase(cafeWords)).toBe('café.latte');
+    expect(toPathCase(cafeWords)).toBe('café/latte');
+
+    const multiAccented = extractWords('Café & Restaurant');
+    expect(multiAccented).toEqual(['Café', 'Restaurant']);
+    expect(toCamelCase(multiAccented)).toBe('caféRestaurant');
+    expect(toSnakeCase(multiAccented)).toBe('café_restaurant');
+  });
+
+  it('handles words written entirely in non-Latin scripts', () => {
+    // Cyrillic
+    const cyrillicWords = extractWords('приветМир');
+    expect(cyrillicWords).toEqual(['привет', 'Мир']);
+    expect(toSnakeCase(cyrillicWords)).toBe('привет_мир');
+    expect(toCamelCase(extractWords('привет_мир'))).toBe('приветМир');
+    expect(toPascalCase(cyrillicWords)).toBe('ПриветМир');
+    expect(toConstantCase(cyrillicWords)).toBe('ПРИВЕТ_МИР');
+    expect(toKebabCase(cyrillicWords)).toBe('привет-мир');
+    expect(toSlug('Привет Мир')).toBe('привет-мир');
+
+    // Greek
+    const greekWords = extractWords('γειαΣου');
+    expect(greekWords).toEqual(['γεια', 'Σου']);
+    expect(toSnakeCase(greekWords)).toBe('γεια_σου');
+    expect(toPascalCase(greekWords)).toBe('ΓειαΣου');
+  });
+
+  it('detects casing correctly for international text', () => {
+    expect(detectCasing('caféLatte')).toBe('camelCase');
+    expect(detectCasing('CaféLatte')).toBe('PascalCase');
+    expect(detectCasing('café_latte')).toBe('snake_case');
+    expect(detectCasing('CAFÉ_LATTE')).toBe('CONSTANT_CASE');
+    expect(detectCasing('приветМир')).toBe('camelCase');
+    expect(detectCasing('привет_мир')).toBe('snake_case');
+  });
+});
diff --git a/src/tools/case-converter/caseConverter.ts b/src/tools/case-converter/caseConverter.ts
new file mode 100644
index 0000000..7b77847
--- /dev/null
+++ b/src/tools/case-converter/caseConverter.ts
@@ -0,0 +1,130 @@
+export interface CaseResult {
+  id: string;
+  name: string;
+  example: string;
+  value: string;
+}
+
+/**
+ * Splits any string into constituent lowercase words based on standard casing conventions:
+ * camelCase, PascalCase, snake_case, kebab-case, dots, slashes, spaces.
+ */
+export function extractWords(input: string): string[] {
+  if (!input || !input.trim()) return [];
+
+  // 1. Separate camelCase/PascalCase boundaries (including Unicode letters)
+  // e.g. "caféLatte" -> "café Latte", "приветМир" -> "привет Мир", "XMLHttpRequest" -> "XML Http Request"
+  const separated = input
+    .replace(/([\p{Ll}\p{N}])([\p{Lu}\p{Lt}])/gu, '$1 $2')
+    .replace(/([\p{Lu}\p{Lt}]+)([\p{Lu}\p{Lt}][\p{Ll}])/gu, '$1 $2');
+
+  // 2. Extract words composed of Unicode letters and numbers
+  const matches = separated.match(/[\p{L}\p{N}]+/gu);
+  return matches || [];
+}
+
+export function toCamelCase(words: string[]): string {
+  if (words.length === 0) return '';
+  return words
+    .map((w, i) => {
+      const lower = w.toLowerCase();
+      return i === 0 ? lower : lower.charAt(0).toUpperCase() + lower.slice(1);
+    })
+    .join('');
+}
+
+export function toPascalCase(words: string[]): string {
+  return words
+    .map((w) => {
+      const lower = w.toLowerCase();
+      return lower.charAt(0).toUpperCase() + lower.slice(1);
+    })
+    .join('');
+}
+
+export function toSnakeCase(words: string[]): string {
+  return words.map((w) => w.toLowerCase()).join('_');
+}
+
+export function toConstantCase(words: string[]): string {
+  return words.map((w) => w.toUpperCase()).join('_');
+}
+
+export function toKebabCase(words: string[]): string {
+  return words.map((w) => w.toLowerCase()).join('-');
+}
+
+export function toTitleCase(words: string[]): string {
+  return words
+    .map((w) => {
+      const lower = w.toLowerCase();
+      return lower.charAt(0).toUpperCase() + lower.slice(1);
+    })
+    .join(' ');
+}
+
+export function toSentenceCase(words: string[]): string {
+  if (words.length === 0) return '';
+  const full = words.map((w) => w.toLowerCase()).join(' ');
+  return full.charAt(0).toUpperCase() + full.slice(1);
+}
+
+export function toDotCase(words: string[]): string {
+  return words.map((w) => w.toLowerCase()).join('.');
+}
+
+export function toPathCase(words: string[]): string {
+  return words.map((w) => w.toLowerCase()).join('/');
+}
+
+export function toSlug(input: string): string {
+  if (!input) return '';
+  return input
+    .normalize('NFD') // normalize unicode
+    .replace(/[\u0300-\u036f]/g, '') // strip Latin diacritics (é -> e, ñ -> n)
+    .toLowerCase()
+    .trim()
+    .replace(/[^\p{L}\p{N}\s\-_]/gu, '') // preserve letters & digits across scripts, strip punctuation
+    .replace(/[\s_]+/g, '-') // spaces and underscores to hyphens
+    .replace(/-+/g, '-') // collapse consecutive hyphens
+    .replace(/^-+|-+$/g, ''); // trim leading/trailing hyphens
+}
+
+export function detectCasing(input: string): string {
+  const trimmed = input.trim();
+  if (!trimmed) return 'Unknown';
+
+  if (/^[\p{Ll}]+(?:[\p{Lu}\p{Lt}][\p{Ll}\p{N}]*)+$/u.test(trimmed)) return 'camelCase';
+  if (/^[\p{Lu}\p{Lt}][\p{Ll}\p{N}]+(?:[\p{Lu}\p{Lt}][\p{Ll}\p{N}]*)+$/u.test(trimmed)) return 'PascalCase';
+  if (/^[\p{Ll}\p{N}]+(?:_[\p{Ll}\p{N}]+)+$/u.test(trimmed)) return 'snake_case';
+  if (/^[\p{Lu}\p{Lt}\p{N}]+(?:_[\p{Lu}\p{Lt}\p{N}]+)+$/u.test(trimmed)) return 'CONSTANT_CASE';
+  if (/^[\p{Ll}\p{N}]+(?:-[\p{Ll}\p{N}]+)+$/u.test(trimmed)) return 'kebab-case';
+  if (/^[\p{Ll}\p{N}]+(?:\.[\p{Ll}\p{N}]+)+$/u.test(trimmed)) return 'dot.case';
+  if (/^[\p{Ll}\p{N}]+(?:\/[\p{Ll}\p{N}]+)+$/u.test(trimmed)) return 'path/case';
+
+  // Explicit single-word formats
+  if (/^[\p{Lu}\p{Lt}][\p{Ll}\p{N}]*$/u.test(trimmed)) return 'Capitalized';
+  if (/^[\p{Ll}\p{N}]+$/u.test(trimmed)) return 'lowercase';
+  if (/^[\p{Lu}\p{Lt}\p{N}]+$/u.test(trimmed)) return 'UPPERCASE';
+
+  return 'Natural text';
+}
+
+export function convertAllCases(input: string): CaseResult[] {
+  const words = extractWords(input);
+
+  return [
+    { id: 'camel', name: 'camelCase', example: 'myVariableName', value: toCamelCase(words) },
+    { id: 'pascal', name: 'PascalCase', example: 'MyVariableName', value: toPascalCase(words) },
+    { id: 'snake', name: 'snake_case', example: 'my_variable_name', value: toSnakeCase(words) },
+    { id: 'constant', name: 'CONSTANT_CASE', example: 'MY_VARIABLE_NAME', value: toConstantCase(words) },
+    { id: 'kebab', name: 'kebab-case', example: 'my-variable-name', value: toKebabCase(words) },
+    { id: 'slug', name: 'URL Slug', example: 'my-article-title-2026', value: toSlug(input) },
+    { id: 'title', name: 'Title Case', example: 'My Variable Name', value: toTitleCase(words) },
+    { id: 'sentence', name: 'Sentence case', example: 'My variable name', value: toSentenceCase(words) },
+    { id: 'dot', name: 'dot.case', example: 'my.variable.name', value: toDotCase(words) },
+    { id: 'path', name: 'path/case', example: 'my/variable/name', value: toPathCase(words) },
+    { id: 'lower', name: 'lowercase', example: 'my variable name', value: input.toLowerCase() },
+    { id: 'upper', name: 'UPPERCASE', example: 'MY VARIABLE NAME', value: input.toUpperCase() },
+  ];
+}
diff --git a/src/tools/case-converter/caseConverterTool.test.tsx b/src/tools/case-converter/caseConverterTool.test.tsx
new file mode 100644
index 0000000..79c2f34
--- /dev/null
+++ b/src/tools/case-converter/caseConverterTool.test.tsx
@@ -0,0 +1,133 @@
+import { describe, it, expect, beforeEach, afterEach, vi } from 'vitest';
+import { act } from 'react';
+import { createRoot, type Root } from 'react-dom/client';
+import { MemoryRouter, Route, Routes } from 'react-router-dom';
+import { ToastProvider } from '../../components/ui/Toast';
+import CaseConverterTool from './CaseConverterTool';
+
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+(globalThis as any).IS_REACT_ACT_ENVIRONMENT = true;
+
+describe('CaseConverterTool Component', () => {
+  let container: HTMLDivElement;
+  let root: Root;
+
+  beforeEach(() => {
+    container = document.createElement('div');
+    document.body.appendChild(container);
+    root = createRoot(container);
+  });
+
+  afterEach(() => {
+    act(() => {
+      root.unmount();
+    });
+    container.remove();
+    vi.restoreAllMocks();
+  });
+
+  const renderTool = (initialPath = '/tools/case-converter') => {
+    act(() => {
+      root.render(
+        <ToastProvider>
+          <MemoryRouter initialEntries={[initialPath]}>
+            <Routes>
+              <Route path="/tools/:slug" element={<CaseConverterTool />} />
+            </Routes>
+          </MemoryRouter>
+        </ToastProvider>
+      );
+    });
+  };
+
+  it('renders the initial layout with default input and format cards', () => {
+    renderTool();
+
+    expect(container.textContent).toContain('Text Case Converter & Slug');
+    expect(container.textContent).toContain('camelCase');
+    expect(container.textContent).toContain('snake_case');
+    expect(container.textContent).toContain('kebab-case');
+    expect(container.textContent).toContain('URL Slug');
+
+    const textarea = container.querySelector('textarea') as HTMLTextAreaElement;
+    expect(textarea).not.toBeNull();
+    expect(textarea.value).toBe('hello_world_example');
+  });
+
+  it('updates converted outputs dynamically when input value changes', () => {
+    renderTool();
+
+    const textarea = container.querySelector('textarea') as HTMLTextAreaElement;
+    expect(textarea).not.toBeNull();
+
+    act(() => {
+      const nativeTextareaValueSetter = Object.getOwnPropertyDescriptor(
+        window.HTMLTextAreaElement.prototype,
+        'value'
+      )?.set;
+      nativeTextareaValueSetter?.call(textarea, 'quickBrownFox');
+      textarea.dispatchEvent(new Event('input', { bubbles: true }));
+      textarea.dispatchEvent(new Event('change', { bubbles: true }));
+    });
+
+    expect(container.textContent).toContain('quick_brown_fox');
+    expect(container.textContent).toContain('quick-brown-fox');
+    expect(container.textContent).toContain('QUICK_BROWN_FOX');
+  });
+
+  it('loads sample texts when sample buttons are clicked', () => {
+    renderTool();
+
+    const sampleButtons = Array.from(container.querySelectorAll('button')).filter((b) =>
+      b.textContent?.includes('APIResponseHandler')
+    );
+    expect(sampleButtons.length).toBeGreaterThan(0);
+
+    act(() => {
+      sampleButtons[0].click();
+    });
+
+    const textarea = container.querySelector('textarea') as HTMLTextAreaElement;
+    expect(textarea.value).toBe('APIResponseHandler');
+    expect(container.textContent).toContain('api_response_handler');
+  });
+
+  it('switches to Batch multi-line mode and transforms text', () => {
+    renderTool();
+
+    const batchButton = Array.from(container.querySelectorAll('button')).find((b) =>
+      b.textContent?.includes('Batch Multi-Line')
+    );
+    expect(batchButton).toBeDefined();
+
+    act(() => {
+      batchButton?.click();
+    });
+
+    expect(container.textContent).toContain('Convert all lines to:');
+
+    const textareas = container.querySelectorAll('textarea');
+    expect(textareas.length).toBeGreaterThanOrEqual(2);
+
+    const inputTextarea = textareas[0];
+    act(() => {
+      const nativeTextareaValueSetter = Object.getOwnPropertyDescriptor(
+        window.HTMLTextAreaElement.prototype,
+        'value'
+      )?.set;
+      nativeTextareaValueSetter?.call(inputTextarea, 'first_item\nsecond_item\nthird_item');
+      inputTextarea.dispatchEvent(new Event('input', { bubbles: true }));
+      inputTextarea.dispatchEvent(new Event('change', { bubbles: true }));
+    });
+
+    const outputTextarea = textareas[1];
+    expect(outputTextarea.value).toContain('firstItem');
+    expect(outputTextarea.value).toContain('secondItem');
+    expect(outputTextarea.value).toContain('thirdItem');
+  });
+
+  it('displays detected casing badge for input', () => {
+    renderTool();
+    expect(container.textContent).toContain('Detected: snake_case');
+  });
+});
diff --git a/src/tools/registry.tsx b/src/tools/registry.tsx
index c7658b2..43309c6 100644
--- a/src/tools/registry.tsx
+++ b/src/tools/registry.tsx
@@ -16,7 +16,8 @@ import {
   Code2,
   Globe2,
   QrCode,
-  FileText
+  FileText,
+  Type,
 } from 'lucide-react';
 
 export interface ToolMeta {
@@ -183,6 +184,15 @@ export const tools: ToolMeta[] = [
     tint: 'linear-gradient(135deg, #bfdbfe, #c4b5fd)',
     Component: lazy(() => import('./markdown/MarkdownTool')),
   },
+  {
+    slug: 'case-converter',
+    title: 'Text Case Converter & Slug',
+    short: 'camel, snake, kebab & slugs',
+    description: 'Transform text between camelCase, PascalCase, snake_case, kebab-case, and URL slugs.',
+    icon: <Type size={22} strokeWidth={1.5} color="var(--ink)" />,
+    tint: 'linear-gradient(135deg, #fed7aa, #f472b6)',
+    Component: lazy(() => import('./case-converter/CaseConverterTool')),
+  },
 ];
 
 export const toolBySlug = (slug: string): ToolMeta | undefined =>