I am personally a big fan of "BALSAMIQ MOCKUPS", it is mostly drag and drop and you can download many layouts from web. When creating some high fidelity mockups I use photoshop also with it, to create subsections.
Sketch 3 Professional digital design for Mac.
Draftium Turbo prototyping tool for websites 🚀
Whimsical Wireframes Lightning fast wireframing with real-time collaboration.