KISSlicer
KISSlicer is a powerful, easy-to-use, and fast cross-platform app that slices STL files into printer-ready G-code files. Keep It Simple Slicer - KISS!
18 Alternatives To KISSlicer
MatterControl
MatterControl is a free, open source app that lets you organize and manage your 3D prints.
OctoPrint
OctoPrint is the snappy web interface for your 3D printer that allows you to control and monitor all aspects of your printer and print jobs, right from your browser.
Onshape
Onshape is the first full-cloud 3D CAD system. It runs in a web browser and on any mobile device.
SliceCrafter
SliceCrafter is an online version of slicing technology that is less powerful than IceSL-slicer but runs completely from within the web browser.