KeepingYouAwake is a small menu bar utility for macOS (Version 10.12 and newer) that can prevent your Mac from entering sleep mode for a predefined duration or as long as it is activated. The app is a small wrapper around Apple's caffeinate command line utility. All current versions of macOS ship with this tool by default. On a MacBook this only works as long as the lid is open. This utility will not harm your Mac because it is based on an official command line tool by Apple.