See what your part contains.
Review source units, transferred faces and inspection coverage in one place.
In the local workspace, select a STEP file and inspection starts automatically. You can also open a saved report.
Read the geometry counts and topology check, then review inspection coverage.
Export the report with its source hash and engine details.
Compare two STEP files · In development
Run this tool in the updated local Mac workspace. STEP files stay on your computer.
Open a saved comparison, then select both STEP files to check their identity. Files stay in this browser.
Choose the older model as baseline and the newer model as candidate, then run the comparison.
One closed solid per file, up to 32 MiB each. Models use their original coordinates; align them in CAD before comparison if needed. Results describe Boolean volume differences, without a conformity decision.
Removed material
Added material
Volume by region
Region numbers follow this calculation’s recorded order. They do not identify the same region in another calculation.
Sorting and filtering change this table only. Totals and exports include both directions; exports keep recorded order. Use the separate 3D controls to change visibility.
| Direction | Region | Volume (mm³) | Recorded status |
|---|
Coral: removed material · Teal: added material. Both use the same import coordinates.
3D selection and navigation help
Click a visible region or choose it from the list to highlight it in amber. Click the background to clear the highlight. These region numbers belong to the current 3D calculation and may differ from the saved report.
Previous and Next follow this 3D list and skip hidden material groups. They also work while showing only one region. Use Fit highlighted region to center the selected region.
Display approximation · 0.1 mm mesher setting, not a certified error bound. Recomputed from both selected STEP files; recorded source identities and volume observations must match. Original reports and notes stay unchanged.
Zero means the kernel observed no solid-volume difference. Surface, PMI and tolerance changes still require review. Use the separate 3D action to review observed volume regions.
Keep observations and follow-up questions with this comparison. Download the review to keep your notes; nothing is saved automatically.
CSV includes all recorded regions and source hashes, regardless of the 3D view. Spreadsheet apps may round numbers; keep the JSON as your original record.
Source evidence and calculation record
Numerical error is estimated, not certified. Source checks establish file identity; they do not authenticate saved calculations. Difference records are separate from inventory sessions.
Inspection finished. Review the results below or select another STEP file.
Compare observations · In development
The selected report is the candidate. Choose another open report as the baseline.
Open a second report or inspect another STEP file to compare their recorded results.
Baseline
Candidate
Drag to rotate, scroll to zoom. Keyboard: arrow keys rotate, +/− zoom, 0 resets. Face matching is not performed.
| Observation | Baseline | Candidate | Difference (candidate − baseline) |
|---|
Recorded values only. Matching numbers do not establish CAD equivalence. X/Y/Z extents use each import's axes; models are not aligned.
Source evidence and calculation scope
Differences use the unrounded recorded numbers. Their numerical uncertainty is not certified. Download JSON to retain full values; this comparison file cannot be reopened as an inventory report.
Part properties · Preview
Single closed solid · CAD geometry. X/Y/Z dimensions follow the import axes; they are not drawing dimensions or an equivalence check.
Raw values and calculation details
Integration errors are numerical estimates, not certified bounds. Volume is not mass; no material density has been assigned.
3D view
CSV uses raw values and English column names. Spreadsheet apps may round numbers; keep the JSON as your original record.
Includes model geometry and face results. Reopen with Open report.
Click to select a face · Drag to rotate · Scroll to zoom · Display approximation.
Calculation details
The engine calculates area from the CAD face. Face numbers apply only to this preview job; selecting a face does not recalculate its values.
Face results · Preview
Select a face to review its details. Displayed values are rounded; the JSON and CSV retain raw values. Face numbers apply only to this preview.
| Face | Surface type | Area status | Area from CAD | Analytic parameters |
|---|
Inspection coverage
Result types remain distinctSource and evidence
Reader diagnostics · Preview
Recorded load syntax and last transfer checks only. Zero recorded failures do not prove complete source coverage or CAD equivalence. Unavailable counts remain unknown; ≥ marks a lower bound when the 256-entry limit is reached.
| Phase | Capture state | Failures | Warnings |
|---|
Entries below contain recorded failures or warnings. Reader model indexes belong to this import; they are not STEP labels or persistent face identities. Message text is not captured.
| Phase | Reader model index | Failures | Warnings |
|---|
Source file evidence
Source file evidence
Optional: compare a STEP file with this report’s recorded source. This does not start a new geometry inspection.
This checks file identity. Geometry and report authenticity remain separate checks.
View original report
Tested engine. Scoped results.
Each file report shows the checks performed on that file and the areas not yet evaluated.
6 September 2026 · OCCT 7.9.3 · Apple Silicon. Synthetic geometry and a public CATIA reference passed the automated geometry suite. This records that development run; it does not certify your part.