diff --git a/src/js/radius/radius.test.ts b/src/js/radius/radius.test.ts
new file mode 100644
index 0000000..bdae53b
--- /dev/null
+++ b/src/js/radius/radius.test.ts
@@ -0,0 +1,38 @@
+import type { RadiusToken } from './radius';
+import { radius } from './radius';
+
+describe('radius', () => {
+  it('should have the correct number of tokens', () => {
+    expect(Object.keys(radius)).toHaveLength(8);
+  });
+
+  it('should have the correct token names', () => {
+    const expectedTokens: RadiusToken[] = [
+      'none',
+      'sm',
+      'md',
+      'lg',
+      'xl',
+      '2xl',
+      '3xl',
+      'full',
+    ];
+    expect(Object.keys(radius)).toEqual(expectedTokens);
+  });
+
+  it('should have the correct values for each token', () => {
+    expect(radius.none).toBe('0');
+    expect(radius.sm).toBe('0.125rem');
+    expect(radius.md).toBe('0.25rem');
+    expect(radius.lg).toBe('0.5rem');
+    expect(radius.xl).toBe('1rem');
+    expect(radius['2xl']).toBe('1.5rem');
+    expect(radius['3xl']).toBe('2rem');
+    expect(radius.full).toBe('9999px');
+  });
+
+  it('should not allow adding new properties', () => {
+    // @ts-expect-error
+    expect(() => (radius.newProperty = '1px')).toThrow();
+  });
+});