There is a 99% uptime guarantee for free accounts, but in the case of 000Webhost, you'll have to consider that there's an enforced one-hour sleep period per day.
Kukhona isiqinisekiso se-99% sokuphumula se-akhawunti yamahhala, kodwa esimweni se-000Webhost, kuzodingeka ucabange ukuthi kunenkathi yokulala yehora elilodwa eliphoqelelwe ngosuku.