diff --git a/src/services/models/Operation.ts b/src/services/models/Operation.ts
index f6fa04ee..9059d346 100644
--- a/src/services/models/Operation.ts
+++ b/src/services/models/Operation.ts
@@ -10,7 +10,9 @@ import { OpenAPIExternalDocumentation, OpenAPIServer } from '../../types';
 
 import {
   getOperationSummary,
+  getStatusCodeType,
   isAbsolutePath,
+  isStatusCode,
   JsonPointer,
   mergeParams,
   sortByRequired,
@@ -99,10 +101,15 @@ export class OperationModel implements IMenuItem {
     let hasSuccessResponses = false;
     this.responses = Object.keys(operationSpec.responses || [])
       .filter(code => {
-        if (parseInt(code, 10) >= 100 && parseInt(code, 10) <= 399) {
+        if (code === 'default') {
+          return true;
+        }
+
+        if (getStatusCodeType(code) === 'success') {
           hasSuccessResponses = true;
         }
-        return isNumeric(code) || code === 'default';
+
+        return isStatusCode(code);
       }) // filter out other props (e.g. x-props)
       .map(code => {
         return new ResponseModel(
diff --git a/src/utils/openapi.ts b/src/utils/openapi.ts
index e5ef8872..a5aeec9a 100644
--- a/src/utils/openapi.ts
+++ b/src/utils/openapi.ts
@@ -6,21 +6,35 @@ import {
   OpenAPISchema,
   Referenced,
 } from '../types';
+import { isNumeric } from './helpers';
 
-export function getStatusCodeType(statusCode: string | number, defaultAsError = false): string {
+function isWildcardStatusCode(statusCode: string | number): statusCode is string {
+  return typeof statusCode === 'string' && /\dxx/i.test(statusCode);
+}
+
+export function isStatusCode(statusCode: string) {
+  return statusCode === 'default' || isNumeric(statusCode) || isWildcardStatusCode(statusCode);
+}
+
+export function getStatusCodeType(statusCode: string, defaultAsError = false): string {
   if (statusCode === 'default') {
     return defaultAsError ? 'error' : 'success';
   }
 
-  if (statusCode < 100 || statusCode > 599) {
+  let code = parseInt(statusCode, 10);
+  if (isWildcardStatusCode(statusCode)) {
+    code *= 100; // parseInt('2xx') parses to 2
+  }
+
+  if (code < 100 || code > 599) {
     throw new Error('invalid HTTP code');
   }
   let res = 'success';
-  if (statusCode >= 300 && statusCode < 400) {
+  if (code >= 300 && code < 400) {
     res = 'redirect';
-  } else if (statusCode >= 400) {
+  } else if (code >= 400) {
     res = 'error';
-  } else if (statusCode < 200) {
+  } else if (code < 200) {
     res = 'info';
   }
   return res;