FinalCheck is a Blender addon from Omine built to catch project mistakes before you commit to a render. Open the Sidebar in the 3D Viewport, open the FinalCheck panel, and press Check; a list of problematic items appears, and you can fix problems at once.
The addon compares viewport and render visibility for collections, objects, instancers, and modifiers, and flags missing image files, an unset render region, Resolution% below 100%, and render samples lower than preview samples. It also checks particle emitter visibility, child amount, and viewport display amount, along with Grease Pencil modifiers and effects. A Preferences sub-panel lets you toggle which items are checked, with settings saved automatically, and you can limit checks to the current scene and view layer or run them across all scenes. Checking automatically when rendering is available too.
FinalCheck is compatible with Blender 2.90 or later, tested up to Blender 4.5.3 as of October 2025, and works with Cycles and Eevee. It's available in English and Japanese under the MIT license.