# How do I check an IFC model?

Add up to five IFC models on Check, or try the sample model, pick a test and run the check. Results then shows the Model Correctness Index with how many elements were tested, a row for each model and a result for every element.

Updated 1 November 2026

## Check a model, step by step

1. Open **Check** in the top bar.
   ![The Check page, with Check outlined in the top bar](https://ifcchecker.com/help/pictures/check-a-model/open-check.webp)
2. Drop the `.ifc` files on the IFC Checker mark, or anywhere on the page, or click the mark and choose them. Without a model of your own, choose **Try the sample model**. [More on adding models](https://ifcchecker.com/help/add-models/).
   ![The Try the sample model button outlined under the drop area](https://ifcchecker.com/help/pictures/check-a-model/try-sample.webp)
3. Under **Tests**, pick a test: your IDS, [a predefined test and its stage](https://ifcchecker.com/help/predefined-tests/), or none. To check against your own IDS, drop the `.ids` file with the model. [More on picking the test](https://ifcchecker.com/help/pick-a-test/).
   ![The Tests table with IFC Checker sample checks picked](https://ifcchecker.com/help/pictures/check-a-model/pick-test.webp)
4. Keep **Model health** ticked to [check the file itself](https://ifcchecker.com/help/model-health/) as well. Look at the line above the button: it says what the check will do.
5. Choose **Run checker**. **Results** opens and shows the check while it runs: a bar on each model's row says which step the check is in. To stop it, choose **Stop check**.
   ![Run checker pressed, and the results filling in with the index, the counts and the model in 3D](https://ifcchecker.com/help/pictures/check-a-model/run-check.webp)
6. Read the [Model Correctness Index](https://ifcchecker.com/help/model-correctness-index/) and the counts under it: untested, failed and passed. With several models, the index counts all of them, and the **Model** table gives each model's own.
7. Read [the result of every element](https://ifcchecker.com/help/read-the-results/), and [export the issues](https://ifcchecker.com/help/export-results/) to fix them. With several models, first choose the model's name in the **Model** table: its elements then show alone. The downloads are under the table.

## What you can check

Check takes IFC files in the STEP format ([What is IFC?](https://ifcchecker.com/help/what-is-ifc/)), the `.ifc` files authoring tools export, and IDS files ([What is IDS?](https://ifcchecker.com/help/what-is-ids/)), the `.ids` files that hold requirements. One check takes up to five models, added together or one by one, and checks them one after another against the same test. A sixth model is not added, and the notice names it.

Note: A model you checked before, with the same test, shows its earlier results at once, and says so. [What if I check a model again?](https://ifcchecker.com/help/checked-before/)

## Check it again

After fixing the model in the authoring tool, export it again. On **Check**, add the new export under the same file name: it takes the place of the old one in the list, also when it was saved over the old file. Under another name it is added beside the old one, so remove the old one first. A corrected IDS added again under its name takes the place of the old one in the same way. The test you picked stays picked. Choose **Run checker** again to see the new result. The **Previous** column of the **Model** table then shows the index of the earlier check beside the new one.

## If something goes wrong

A file that is refused, a check that does not finish or a model that cannot be read: [why was my file refused or not read?](https://ifcchecker.com/help/troubleshooting-file-refused/). A 3D view that is empty or slow: [troubleshooting the 3D view](https://ifcchecker.com/help/troubleshooting-3d-view/).

## Keep reading

Next: [What does the Model Correctness Index mean?](https://ifcchecker.com/help/model-correctness-index/)

Related:

- [What is on the main screen?](https://ifcchecker.com/help/main-screen/)
- [How do I add my models to a check?](https://ifcchecker.com/help/add-models/)
- [How do I pick a test?](https://ifcchecker.com/help/pick-a-test/)
- [How is the Results page laid out?](https://ifcchecker.com/help/read-the-results/)

[Workflows and help](https://ifcchecker.com/help/) / [Getting started](https://ifcchecker.com/help/collections/start/)