diff --git a/src/lib/utils/conversions.test.ts b/src/lib/utils/conversions.test.ts
new file mode 100644
index 0000000..1a7c532
--- /dev/null
+++ b/src/lib/utils/conversions.test.ts
@@ -0,0 +1,50 @@
+import { describe, it, expect } from 'vitest';
+import { cmToFeetInches, feetInchesToCm, kgToLb, lbToKg } from './conversions';
+
+describe('cmToFeetInches', () => {
+	it('converts 180 cm', () => {
+		expect(cmToFeetInches(180)).toBe('5\'11"');
+	});
+
+	it('converts 152 cm', () => {
+		expect(cmToFeetInches(152)).toBe('5\'0"');
+	});
+
+	it('converts 0 cm', () => {
+		expect(cmToFeetInches(0)).toBe('0\'0"');
+	});
+
+	it('converts 30 cm (just inches)', () => {
+		expect(cmToFeetInches(30)).toBe('1\'0"');
+	});
+});
+
+describe('feetInchesToCm', () => {
+	it('converts 5\'11" back', () => {
+		expect(feetInchesToCm(5, 11)).toBeCloseTo(180.34, 0);
+	});
+
+	it('converts 0\'0"', () => {
+		expect(feetInchesToCm(0, 0)).toBe(0);
+	});
+});
+
+describe('kgToLb', () => {
+	it('converts 75 kg', () => {
+		expect(kgToLb(75)).toBeCloseTo(165.35, 0);
+	});
+
+	it('converts 0 kg', () => {
+		expect(kgToLb(0)).toBe(0);
+	});
+});
+
+describe('lbToKg', () => {
+	it('converts 165 lb', () => {
+		expect(lbToKg(165)).toBeCloseTo(74.84, 0);
+	});
+
+	it('converts 0 lb', () => {
+		expect(lbToKg(0)).toBe(0);
+	});
+});
diff --git a/src/lib/utils/conversions.ts b/src/lib/utils/conversions.ts
new file mode 100644
index 0000000..9655ccf
--- /dev/null
+++ b/src/lib/utils/conversions.ts
@@ -0,0 +1,22 @@
+const CM_PER_INCH = 2.54;
+const INCHES_PER_FOOT = 12;
+const LB_PER_KG = 2.20462;
+
+export function cmToFeetInches(cm: number): string {
+	const totalInches = Math.round(cm / CM_PER_INCH);
+	const feet = Math.floor(totalInches / INCHES_PER_FOOT);
+	const inches = totalInches % INCHES_PER_FOOT;
+	return `${feet}'${inches}"`;
+}
+
+export function feetInchesToCm(feet: number, inches: number): number {
+	return (feet * INCHES_PER_FOOT + inches) * CM_PER_INCH;
+}
+
+export function kgToLb(kg: number): number {
+	return kg * LB_PER_KG;
+}
+
+export function lbToKg(lb: number): number {
+	return lb / LB_PER_KG;
+}
diff --git a/src/lib/utils/dates.test.ts b/src/lib/utils/dates.test.ts
new file mode 100644
index 0000000..06b148e
--- /dev/null
+++ b/src/lib/utils/dates.test.ts
@@ -0,0 +1,33 @@
+import { describe, it, expect } from 'vitest';
+import { icYear, formatICDate } from './dates';
+
+describe('icYear', () => {
+	it('adds 442 to the real year', () => {
+		expect(icYear(2026)).toBe(2468);
+	});
+
+	it('works for other years', () => {
+		expect(icYear(2000)).toBe(2442);
+	});
+});
+
+describe('formatICDate', () => {
+	it('formats with ordinal suffixes', () => {
+		expect(formatICDate(new Date(2026, 2, 1))).toBe('March 1st, 2468');
+		expect(formatICDate(new Date(2026, 2, 2))).toBe('March 2nd, 2468');
+		expect(formatICDate(new Date(2026, 2, 3))).toBe('March 3rd, 2468');
+		expect(formatICDate(new Date(2026, 2, 4))).toBe('March 4th, 2468');
+	});
+
+	it('handles 11th, 12th, 13th', () => {
+		expect(formatICDate(new Date(2026, 0, 11))).toBe('January 11th, 2468');
+		expect(formatICDate(new Date(2026, 0, 12))).toBe('January 12th, 2468');
+		expect(formatICDate(new Date(2026, 0, 13))).toBe('January 13th, 2468');
+	});
+
+	it('handles 21st, 22nd, 23rd', () => {
+		expect(formatICDate(new Date(2026, 5, 21))).toBe('June 21st, 2468');
+		expect(formatICDate(new Date(2026, 5, 22))).toBe('June 22nd, 2468');
+		expect(formatICDate(new Date(2026, 5, 23))).toBe('June 23rd, 2468');
+	});
+});
diff --git a/src/lib/utils/dates.ts b/src/lib/utils/dates.ts
new file mode 100644
index 0000000..c68a1df
--- /dev/null
+++ b/src/lib/utils/dates.ts
@@ -0,0 +1,24 @@
+const IC_OFFSET = 442;
+
+const MONTHS = [
+	'January', 'February', 'March', 'April', 'May', 'June',
+	'July', 'August', 'September', 'October', 'November', 'December'
+];
+
+function ordinal(n: number): string {
+	if (n >= 11 && n <= 13) return n + 'th';
+	switch (n % 10) {
+		case 1: return n + 'st';
+		case 2: return n + 'nd';
+		case 3: return n + 'rd';
+		default: return n + 'th';
+	}
+}
+
+export function icYear(realYear: number): number {
+	return realYear + IC_OFFSET;
+}
+
+export function formatICDate(date: Date): string {
+	return `${MONTHS[date.getMonth()]} ${ordinal(date.getDate())}, ${icYear(date.getFullYear())}`;
+}