diff --git a/packages/core/workers/src/WorkerFarm.js b/packages/core/workers/src/WorkerFarm.js
index 1f03474eed2..463502b9033 100644
--- a/packages/core/workers/src/WorkerFarm.js
+++ b/packages/core/workers/src/WorkerFarm.js
@@ -628,7 +628,7 @@ export default class WorkerFarm extends EventEmitter {
   static getNumWorkers(): number {
     return process.env.PARCEL_WORKERS
       ? parseInt(process.env.PARCEL_WORKERS, 10)
-      : Math.ceil(cpuCount() / 2);
+      : Math.min(4, Math.ceil(cpuCount() / 2));
   }
 
   static isWorker(): boolean {