A file that stores a building information model: 3D geometry plus the data attached to it — what each element is, its properties, quantities and relationships. It can be a native authoring file (.rvt, .pln, .db1), an open exchange file (.ifc, .bcf), or a coordination file (.nwd, .smc). 'BIM file' is a category, not one format.

Which BIM file format is best?

There is no single best one — each does a different job. Author and edit in the native format of your tool (RVT, PLN, DB1); exchange with other disciplines and clients as IFC (open, standardised, opens anywhere); review and clash many models together in a coordination format such as NWD or a federated IFC. Problems start when one format is asked to do another's job.

No. DWG stores CAD geometry — lines, blocks, layers — with no building semantics: a wall is a pair of lines, not an object with a fire rating and a volume. DWG remains the standard for 2D drawing deliverables, and BIM tools export drawings to it, but the model itself lives in RVT/PLN/IFC.

How can I open a BIM file without the software that made it?

Ask for an IFC export — every BIM authoring tool produces one — and open it in any IFC viewer; a browser-based viewer needs no install and keeps the file on your machine. Native files are harder: RVT needs Revit (or Autodesk's free viewer for read-only), PLN needs ArchiCAD, NWD needs Navisworks Freedom. If you only ever receive one native format, install that vendor's free viewer.

Is a Power BI .bim file a BIM file?

No, unrelated. A .bim file from Analysis Services, Tabular Editor or Power BI is a JSON definition of a tabular data model (tables, measures, relationships) — the 'BIM' there is Business Intelligence Model. Nothing in the AEC world reads it, and no BIM tool produces it. If you searched for '.bim file' with a spreadsheet problem, that is your answer.

BIM file formats explained: what each one is for and which one to send

Updated August 26, 2026 · by the IFCfiles team

BIM file formats explained — native, open and coordination formats compared

A BIM file stores a building model as objects with data — walls, doors, ducts, each with its geometry, properties and relationships — rather than as lines on a sheet. "BIM file" is not one format, though: it covers native files locked to an authoring tool (.rvt, .pln, .db1), open exchange formats anyone can read (.ifc, .bcf, COBie) and coordination formats for reviewing many models at once (.nwd, .smc). Which one you should send, receive or archive depends entirely on the job.

Three groups of BIM file formats: native authoring, open exchange and coordination/review, with the main extensions in each — Three families, three jobs. Most exchange problems come from using a format outside its column.

Native formats: where models are made

Every authoring tool keeps its model in its own database format. This is where the parametric intelligence lives — the constraints, families, hosted relationships and view definitions that make the model editable — and it is also the least portable thing on the project.

Revit — .rvt (project), .rfa (family), .rte (template). Version-locked: a 2026 file will not open in Revit 2024. Cloud workshared models live in Autodesk Docs and are opened, not "sent".
ArchiCAD — .pln (solo project), .pla (archive with libraries embedded — send this one), .bimproject for Teamwork.
Tekla Structures — .db1 inside a model folder (never a single file; zip the folder). Tekla is also one of the cleanest IFC exporters around.
Bentley — .dgn for MicroStation and OpenBuildings; increasingly iModel in the cloud.
Vectorworks — .vwx; Allplan — .ndw; SketchUp — .skp (geometry-first, BIM data through classifications and extensions).

Rule of thumb: native files travel inside a team, not between disciplines. Sending an .rvt to a consultant who runs ArchiCAD gives them nothing they can open; sending it to another Revit office gives them everything, including things you may not want to hand over.

Open formats: how models move between people

IFC — the model itself

Industry Foundation Classes (.ifc, or zipped .ifczip) is the ISO 16739 open standard: a vendor-neutral, text-based description of the whole model — every object with its type, geometry, property sets, quantities and relationships. Every authoring tool exports it; every viewer, checker and coordination tool reads it; public clients across Europe require it. It is the format that lets a Tekla structure, an ArchiCAD architecture model and a Revit MEP model meet in one place. What it is not is a round-trip editing format — an IFC imported into Revit becomes dumb geometry, which is why converting IFC to Revit is a compromise rather than a conversion. If you are new to it, start with What is an IFC file?; for the file's anatomy and its .ifczip/.ifcxml variants, see the IFC file format explained.

BCF — the issues, not the model

BIM Collaboration Format (.bcf / .bcfzip) carries clash and review comments: a camera viewpoint, a snapshot, the GlobalIds of the elements concerned, a status and a comment thread. It references elements in the model without carrying the model, so a 40 KB BCF can travel between Solibri, Navisworks, BIMcollab and Revit while the 400 MB models stay where they are.

COBie — the data for the operator

COBie is a structured spreadsheet (usually .xlsx) of asset data — spaces, equipment, manufacturers, warranties — extracted from the model for facilities management. It is a subset of IFC data in a table, defined by the buildingSMART Facility Management Handover MVD. When a client asks for "the data", this is often what they mean, and a plain IFC-to-Excel export of properties and quantities is frequently the first step towards it.

glTF, DWG and friends — geometry only

.gltf/.glb is the open 3D format for the web, game engines and AR; converting IFC to glTF keeps the shapes and drops the BIM data by design. .dwg/.dxf is CAD, not BIM: lines and blocks, no objects — still the standard for 2D drawing deliverables. .obj, .fbx, .stl and .3dm are in the same family. Useful, but if someone sends one as "the BIM model", the data did not make the trip.

Coordination formats: many models, one view

Once every discipline has exported, someone has to put the models together, find the clashes and run the review meeting. Coordination formats are optimised for that: fast to load, many models at once, annotate and measure, no editing.

Navisworks — .nwc (a cache exported from each source model), .nwf (a lightweight federation that points at the NWCs) and .nwd (everything baked into one file, opens in the free Navisworks Freedom).
Solibri — .smc, the federated model with its rule checks and issues.
Federated IFC — several discipline IFCs loaded together (BIMcollab Zoom, usBIM, Trimble Connect, most cloud CDEs) or merged into a single IFC when the receiver can only load one file.

Side by side

Format	Type	Carries	Editable	Opens without the authoring tool
RVT / PLN / DB1	Native	Full parametric model	Yes	Only with that vendor's viewer, read-only
IFC / IFCZIP	Open	Objects, properties, quantities, relations	Limited	Yes — any IFC viewer, incl. in a browser
BCF	Open	Issues, viewpoints, element IDs	Yes (comments)	Yes — most BIM tools import it
COBie	Open	Asset data tables	Yes	Yes — Excel
NWD / NWC / SMC	Coordination	Federated geometry + properties	No	Free viewer for NWD; SMC needs Solibri
glTF / GLB	Open (3D)	Geometry, materials	No	Yes — browsers, game engines
DWG / DXF	CAD	2D/3D lines, blocks, layers	Yes	Yes — any CAD viewer; no BIM data

Which one to send

To another discipline for coordination: IFC (agree the version and view — typically IFC4 Reference View or IFC2x3 CV2.0 — and zip it). Send BCF back with the issues.
To a client or public body as a deliverable: whatever the BIM execution plan says, which is almost always IFC plus native, plus COBie at handover.
To a contractor pricing the job: IFC for quantities (or an Excel export of the quantities), DWG/PDF for the drawings.
To a colleague on the same software: the native file — with libraries embedded (.pla, Revit "eTransmit", zipped Tekla folder).
To marketing, a web page or a VR headset: glTF/GLB.
To someone who just needs to look: IFC and a link to a browser viewer — nothing to install, and the model stays on their machine.

Opening BIM files without the authoring software

The honest answer for native formats is "with that vendor's free viewer, read-only": Autodesk Viewer or Revit Viewer mode for RVT, BIMx for ArchiCAD models, Navisworks Freedom for NWD, Trimble Connect for Tekla and SketchUp. It works, but you end up with four viewers and no way to see the models together.

The open answer is to ask for IFC. One format, one viewer, every discipline in the same scene: the free IFC viewer on this site opens IFC2x3 through IFC4x3 in the browser with the spatial tree, properties, sections and measurements, and loads several files at once for a quick federation — without uploading anything, which is the point when the models are under NDA. Our comparison of free IFC viewers covers the desktop alternatives if you prefer an install.

Two things that are not BIM files

.bim from Power BI / Analysis Services. A JSON definition of a tabular data model — "Business Intelligence Model". Same three letters, no relation, and the reason a surprising number of people land on BIM pages with a spreadsheet problem.
PDF drawing sets and DWGs exported from a BIM model. They are deliverables of BIM, not BIM files: the objects and data stayed behind in the model. See IFC vs RVT vs DWG for what each of those actually stores.

In short

Author in the native format, exchange as IFC, review in a coordination format, hand over IFC plus COBie, and keep BCF for the conversation about the model. Agree the list in the BIM execution plan on day one — "IFC4 Reference View, .ifczip, one file per discipline, BCF 2.1 for issues" — and most "which file do you need?" emails disappear.