diff --git a/atom/browser/api/atom_api_session.cc b/atom/browser/api/atom_api_session.cc
index b48071b45de6d..b64e188c29093 100644
--- a/atom/browser/api/atom_api_session.cc
+++ b/atom/browser/api/atom_api_session.cc
@@ -420,6 +420,19 @@ void Session::ResolveProxy(
   browser_context_->GetResolveProxyHelper()->ResolveProxy(url, callback);
 }
 
+void Session::GetCacheSize(const net::CompletionCallback& callback) {
+  content::BrowserContext::GetDefaultStoragePartition(browser_context_.get())
+      ->GetNetworkContext()
+      ->ComputeHttpCacheSize(
+          base::Time(), base::Time::Max(),
+          base::BindOnce(
+              [](const net::CompletionCallback& cb, bool is_upper_bound,
+                 int64_t size_or_error) {
+                cb.Run(net::ErrorToString(size_or_error));
+              },
+              callback));
+}
+
 template <Session::CacheAction action>
 void Session::DoCacheAction(const net::CompletionCallback& callback) {
   base::PostTaskWithTraits(
@@ -748,7 +761,7 @@ void Session::BuildPrototype(v8::Isolate* isolate,
   mate::ObjectTemplateBuilder(isolate, prototype->PrototypeTemplate())
       .MakeDestroyable()
       .SetMethod("resolveProxy", &Session::ResolveProxy)
-      .SetMethod("getCacheSize", &Session::DoCacheAction<CacheAction::STATS>)
+      .SetMethod("getCacheSize", &Session::GetCacheSize)
       .SetMethod("clearCache", &Session::DoCacheAction<CacheAction::CLEAR>)
       .SetMethod("clearStorageData", &Session::ClearStorageData)
       .SetMethod("flushStorageData", &Session::FlushStorageData)
diff --git a/atom/browser/api/atom_api_session.h b/atom/browser/api/atom_api_session.h
index 3a6216a031813..8b4eb06bfbc58 100644
--- a/atom/browser/api/atom_api_session.h
+++ b/atom/browser/api/atom_api_session.h
@@ -66,6 +66,7 @@ class Session : public mate::TrackableObject<Session>,
                     const ResolveProxyHelper::ResolveProxyCallback& callback);
   template <CacheAction action>
   void DoCacheAction(const net::CompletionCallback& callback);
+  void GetCacheSize(const net::CompletionCallback& callback);
   void ClearStorageData(mate::Arguments* args);
   void FlushStorageData();
   void SetProxy(const mate::Dictionary& options, const base::Closure& callback);