I have been using the free plan for Uptime robot for around 10 years now. I run a very small business and have to keep costs to a minimum so this has proved fantastic at monitoring the few websites I look after. The fact they still offer a free plan is amazing and I'm hugely grateful for it. I highly recommend their services and if you can to pay for a plan to help them out even better. I'm hoping to later in the year if I can grow my business.I recently had to call their customer service line and that was excellent too, I got through straight away and the chap solved my problem very quickly.