diff --git a/package.json b/package.json
index 01d33ad..45ac096 100644
--- a/package.json
+++ b/package.json
@@ -1,25 +1,25 @@
 {
-  "name": "vite-template-solid",
-  "version": "0.0.0",
-  "description": "",
-  "scripts": {
-    "start": "vite",
-    "dev": "vite",
-    "build": "vite build",
-    "serve": "vite preview"
-  },
-  "license": "MIT",
-  "devDependencies": {
-    "@typescript-eslint/eslint-plugin": "^6.9.0",
-    "@typescript-eslint/parser": "^6.9.0",
-    "eslint": "^8.52.0",
-    "solid-devtools": "^0.27.3",
-    "typescript": "^5.1.3",
-    "vite": "^4.3.9",
-    "vite-plugin-solid": "^2.7.0"
-  },
-  "dependencies": {
-    "@solidjs/router": "^0.8.3",
-    "solid-js": "^1.7.6"
-  }
+	"name": "vite-template-solid",
+	"version": "0.0.0",
+	"description": "",
+	"scripts": {
+		"start": "vite",
+		"dev": "vite",
+		"build": "vite build",
+		"serve": "vite preview"
+	},
+	"license": "MIT",
+	"devDependencies": {
+		"@typescript-eslint/eslint-plugin": "^6.9.0",
+		"@typescript-eslint/parser": "^6.9.0",
+		"eslint": "^8.52.0",
+		"solid-devtools": "^0.27.3",
+		"typescript": "^5.1.3",
+		"vite": "^4.3.9",
+		"vite-plugin-solid": "^2.7.0"
+	},
+	"dependencies": {
+		"@solidjs/router": "^0.8.3",
+		"solid-js": "^1.7.6"
+	}
 }
diff --git a/src/Navigation.tsx b/src/Navigation.tsx
index bd86cf1..7556bff 100644
--- a/src/Navigation.tsx
+++ b/src/Navigation.tsx
@@ -8,6 +8,7 @@ const Navigation: Component = () => {
 			<A href='/strrev'>String Reverse</A>
 			<A href='/strnoise'>String Noise</A>
 			<A href='/loremipsum'>Lorem Ipsum</A>
+			<A href='/convertbase'>Convert Base</A>
 		</>
 	);
 };
diff --git a/src/index.tsx b/src/index.tsx
index 14be359..610c23d 100644
--- a/src/index.tsx
+++ b/src/index.tsx
@@ -8,6 +8,8 @@ import StrLen from './pages/StrLen';
 import StrRev from './pages/StrRev';
 import StrNoise from './pages/StrNoise';
 import LoremIpsum from './pages/LoremIpsum';
+import Convert from './pages/ConvertBase';
+import ConvertBase from './pages/ConvertBase';
 
 const root = document.getElementById('root');
 
@@ -25,6 +27,7 @@ render(() => (
 			<Route path="/strrev" component={StrRev} />
 			<Route path="/strnoise" component={StrNoise} />
 			<Route path="/loremipsum" component={LoremIpsum} />
+			<Route path="/convertbase" component={ConvertBase} />
 		</Routes>
 	</Router>
 ), root!);
diff --git a/src/pages/ConvertBase.tsx b/src/pages/ConvertBase.tsx
new file mode 100644
index 0000000..348fc23
--- /dev/null
+++ b/src/pages/ConvertBase.tsx
@@ -0,0 +1,102 @@
+import { Component, Setter, createEffect, createSignal, on } from 'solid-js';
+
+import styles from './Page.module.css';
+import Navigation from '../Navigation';
+
+function group(str: string, groupSize: number) {
+	const subs = [];
+	for (let i = 0; i < Math.ceil(str.length / groupSize); i++) {
+		let sub = str.slice(Math.max(0, str.length - i * groupSize - groupSize), str.length - i * groupSize);
+		while (sub.length < groupSize) sub = '0' + sub;
+		subs.push(sub);
+	}
+
+	return subs.reverse().join(' ');
+}
+
+function parse(value: string, base: number) {
+	return [...value].reduce((r, v) => r * BigInt(base) + BigInt(parseInt(v, base)), 0n);
+}
+
+const ConvertBase: Component = () => {
+	const [error, setError] = createSignal(' ');
+	const [value, setValue] = createSignal(BigInt(0));
+	const [decimal, setDecimal] = createSignal('0');
+	const [binary, setBinary] = createSignal('0');
+	const [binaryOctets, setBinaryOctet] = createSignal(true);
+	const [octal, setOctal] = createSignal('0');
+	const [octalTriplets, setOctalTriplet] = createSignal(true);
+	const [hex, setHex] = createSignal('0');
+	const [hexPairs, setHexPairs] = createSignal(true);
+
+	function updateExcept(value: string, base: number, except: Setter<string>) {
+		const raw = value.replaceAll(/ /g, '');
+
+		setError('');
+
+		if (base == 2) { // TODO: common validation method
+			if ([...raw].find(c => !['0', '1'].includes(c))) {
+				setError('Invalid binary number');
+				return;
+			}
+		} else if (base == 8) {
+			if ([...raw].find(c => !['0', '1', '2', '3', '4', '5', '6', '7'].includes(c))) {
+				setError('Invalid octal number');
+				return;
+			}
+		} else if (base == 10) {
+			if ([...raw].find(c => !['0', '1', '2', '3', '4', '5', '6', '7', '8', '9'].includes(c))) {
+				setError('Invalid decimal number');
+				return;
+			}
+		} else if (base == 16) {
+			if ([...raw].find(c => !['0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f', 'A', 'B', 'C', 'D', 'E', 'F'].includes(c))) {
+				setError('Invalid hex number');
+				return;
+			}
+		}
+
+		const num = parse(raw, base);
+
+		setValue(num);
+		if (setDecimal != except) setDecimal(num.toString());
+		if (setBinary != except) setBinary(binaryOctets() ? group(num.toString(2), 8) : num.toString(2));
+		if (setOctal != except) setOctal(octalTriplets() ? group(num.toString(8), 3) : num.toString(8));
+		if (setHex != except) setHex(hexPairs() ? group(num.toString(16), 2) : num.toString(16));
+	}
+
+	createEffect(on(binaryOctets, () => setBinary(binaryOctets() ? group(value().toString(2), 8) : value().toString(2))));
+	createEffect(on(octalTriplets, () => setOctal(octalTriplets() ? group(value().toString(8), 3) : value().toString(8))));
+	createEffect(on(hexPairs, () => setHex(hexPairs() ? group(value().toString(16), 2) : value().toString(16))));
+
+	return (
+		<div class={styles.page}>
+			<h1>Convert</h1>
+			<h2>Bases</h2>
+			<span>{error()}</span>
+			<h3>Decimal</h3>
+			<textarea value={decimal()} oninput={e => updateExcept(e.currentTarget.value, 10, setDecimal)} />
+			<h3>Binary</h3>
+			<textarea value={binary()} oninput={e => updateExcept(e.currentTarget.value, 2, setBinary)} />
+			<div class={styles.checkbox}>
+				<input id={'octets'} type={'checkbox'} checked={binaryOctets()} onchange={e => setBinaryOctet(e.currentTarget.checked)} />
+				<label for={'octets'}>Octets</label>
+			</div>
+			<h3>Octal</h3>
+			<textarea value={octal()} oninput={e => updateExcept(e.currentTarget.value, 8, setOctal)} />
+			<div class={styles.checkbox}>
+				<input id={'triplets'} type={'checkbox'} checked={octalTriplets()} onchange={e => setOctalTriplet(e.currentTarget.checked)} />
+				<label for={'triplets'}>Triplets</label>
+			</div>
+			<textarea value={hex()} oninput={e => updateExcept(e.currentTarget.value, 16, setHex)} />
+			<div class={styles.checkbox}>
+				<input id={'pairs'} type={'checkbox'} checked={hexPairs()} onchange={e => setHexPairs(e.currentTarget.checked)} />
+				<label for={'pairs'}>Pairs</label>
+			</div>
+			<h2>All Tools</h2>
+			<Navigation />
+		</div>
+	);
+};
+
+export default ConvertBase;