diff --git a/src/util.js b/src/util.js
index 8bd989c9..3f4f8663 100644
--- a/src/util.js
+++ b/src/util.js
@@ -30,12 +30,12 @@ export function exec(url, route, opts) {
 				flags = (route[i].match(/[+*?]+$/) || EMPTY)[0] || '',
 				plus = ~flags.indexOf('+'),
 				star = ~flags.indexOf('*'),
-				val = url[i] || '';
+				val = url[i];
 			if (!val && !star && (flags.indexOf('?')<0 || plus)) {
 				ret = false;
 				break;
 			}
-			matches[param] = decodeURIComponent(val);
+			matches[param] = decodeURIComponent(val) || undefined;
 			if (plus || star) {
 				matches[param] = url.slice(i).map(decodeURIComponent).join('/');
 				break;
diff --git a/test/util.test.js b/test/util.test.js
index 04eab7d7..6743c8c6 100644
--- a/test/util.test.js
+++ b/test/util.test.js
@@ -85,10 +85,10 @@ describe('util', () => {
 		});
 
 		it('should match optional param segments', () => {
-			expect(exec('/', '/:foo?', {})).toEqual({ foo:'' });
+			expect(exec('/', '/:foo?', {})).toEqual({ foo:undefined });
 			expect(exec('/bar', '/:foo?', {})).toEqual({ foo:'bar' });
-			expect(exec('/', '/:foo?/:bar?', {})).toEqual({ foo:'', bar:'' });
-			expect(exec('/bar', '/:foo?/:bar?', {})).toEqual({ foo:'bar', bar:'' });
+			expect(exec('/', '/:foo?/:bar?', {})).toEqual({ foo:undefined, bar:undefined });
+			expect(exec('/bar', '/:foo?/:bar?', {})).toEqual({ foo:'bar', bar:undefined });
 			expect(exec('/bar', '/:foo?/bar', {})).toEqual(false);
 			expect(exec('/foo/bar', '/:foo?/bar', {})).toEqual({ foo:'foo' });
 		});