diff --git a/functions/is-problem-json-schema.js b/functions/is-problem-json-schema.js
index 4d71cd4..f69fbd1 100644
--- a/functions/is-problem-json-schema.js
+++ b/functions/is-problem-json-schema.js
@@ -33,7 +33,7 @@ const assertProblemSchema = (schema) => {
   }
   const status = (schema.properties || {}).status || {};
   if (status.type !== 'integer' || status.format !== 'int32') {
-    throw "Problem json must have property 'status' with type 'integer' and format 'in32'";
+    throw "Problem json must have property 'status' with type 'integer' and format 'int32'";
   }
   const detail = (schema.properties || {}).detail || {};
   if (detail.type !== 'string') {