diff --git a/README.md b/README.md
index 00ef1bf..6d06984 100644
--- a/README.md
+++ b/README.md
@@ -22,7 +22,7 @@ Relevant Awesome Lists
 Simulators
 ----------
 
-- [CoppeliaSim](coppeliarobotics.com/index.html) - Create, Simulate, any Robot. (formerly named V-REP)
+- [CoppeliaSim](https://coppeliarobotics.com/index) - Create, Simulate, any Robot. (formerly named V-REP)
 - [Microsoft Airsim](https://github.com/Microsoft/AirSim) - Open source simulator based on Unreal Engine for autonomous vehicles from Microsoft AI & Research.
 - [Bullet Physics SDK](https://github.com/bulletphysics/bullet3) - Real-time collision detection and multi-physics simulation for VR, games, visual effects, robotics, machine learning etc. Also see [pybullet](https://pybullet.org).
 
@@ -73,7 +73,7 @@ Tracking
 Robot Operating System (ROS)
 ----------------------------
 
-- [ROS](ros.org) - Main ROS website.
+- [ROS](https://www.ros.org) - Main ROS website.
 - [ros2/design](https://github.com/ros2/design) - Design documentation for ROS 2.0 effort.