diff --git a/src/utils.js b/src/utils.js
index 809c952..6025efc 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -25,5 +25,5 @@ export function encodeQueryString(data) {
 export function replaceVars(text, vars = {}) {
   if (typeof text !== 'string') return text;
 
-  return text.replace(/{{([\w.-]+)}}/g, (_, key) => vars[key] || '');
+  return text.replace(/{{([\w.-]+)}}/g, (_, key) => vars[key] ?? '');
 };