How many times you wanted to know if an Ethernet plug or port has internet connectivity and you had to bring your laptop or a cable from the next room to check? And how many times the only tools available were the simple Network Cable tester and your provider’s Modem or Router? For me that was a common issue and of course there was no easy, “plug and play” solution (at a reasonable price!!). Taking these into consideration I decided to give a solution by making a simple optimization to the most common Network tool. Arduino Network Tester, extends the functionality of the well-known Network Cable tester by adding DHCP, DNS and Internet connectivity tests using an Arduino Pro Mini and a W5500 Ethernet Shield with an overall cost of less than €15!