ModelDiff compares two versions of a 3D model inside Autodesk® Fusion® and instantly shows you what changed.

Stop squinting at two windows side by side to spot the difference. Geometry that exists only in one version is highlighted in blue, geometry only in the other in orange — click any item in the results list to select and zoom straight to it.

Key features:

• Blue/orange highlighting, deliberately chosen instead of red/green so the colors stay distinguishable for color-blind users
• Compare against another open Fusion document, or a local STEP / IGES / SAT / SMT / F3D file
• One simple dialog: pick the reference model and an alignment method — no cryptic Yes/No prompts
• Six alignment options: same-origin (no correction), 3 planes, cylinder + end face for turned parts, 1 point, datum plane + 2 holes (3-2-1 style, ideal for plates), and 3 points
• While picking alignment faces, only the model you are picking on is shown — no accidental clicks on the wrong model
• Clickable results list labeled with the actual file/document names — holes and fillets shown as Ø/R, other faces by area
• Realign button: if the result doesn't look right, pick another alignment method and redo the comparison without re-picking the reference — in the same comparison tab
• The comparison opens in a separate design tab; your current document is never modified
• English and Japanese UI, follows your Fusion language setting