A client or colleague sent a SketchUp model and you don't have SketchUp installed. Omia opens .skp files in 3D on Mac or Windows — with materials and textures — entirely offline.
Free to view · 5 free saves, conversions & pro-format opens · then $19.90 one-time · no subscription · files never leave your computer

We'd rather you know before downloading.
SketchUp's own viewer and most online viewers want an account or an upload. Omia just opens the file on your machine, which is what you want for client work.
Install Omia (Mac or Windows) and double-click the .skp file. It shows the model in 3D with its materials and textures, read-only.
Viewing files is free forever, with no sign-up. Saving edits, converting, and opening pro formats (DWG, STEP, SketchUp, CorelDRAW) each come with 5 free uses; after that it's a one-time $19.90 licence, no subscription.
No. Omia processes files locally.
No. Omia is a viewer; to edit you still need SketchUp.
Omia also opens: 3D models · DWG & DXF · STEP & STL · 150+ formats in one app