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Open Source / Fragments

Fragments: the open BIM format for the web.

Traditional BIM files are heavy and not built for real-time work. Fragments gives you an open, schema-agnostic foundation you can stream, edit natively and scale, without vendor lock-in.

A structural model streamed as Fragments
What Fragments is

Open, schema-agnostic, built for performance.

Open format (MIT license)Adopt, extend and ship freely.
Schema-agnosticStore any data model, including IFC.
Editable by designProperties and geometry, implicit and explicit.
Performance-firstBinary, lightweight, deduplicated; streams on the web.
What it fixes vs IFC STEP

From text files to a format built for the web.

From text to binaryCompact payloads, instant parsing, web streaming.
Chunked, partial loadingOpen huge projects without waiting for everything.
Native editabilityUpdate data and geometry without lock-in.
DeduplicationTransmit once, reference many times.
Stable IDs, deterministic structureReliable selection, linking and round-trips.
Modern pipelinesIndexing, querying and incremental updates at scale.
Beyond IFC A schema-agnostic backbone.
  • Store IFC inside Fragments to keep semantics and gain performance.
  • Or export Fragments directly from your app and keep your own schema, with no forced translation.
  • Map properties cleanly across viewers, services and analysis tools.
  • Future-proof: evolve your schema without breaking storage.
Use it in your apps From file to product.
  • Load, render and query Fragments with That Open Engine, 100% open source and free.
  • Convert IFC to Fragments in ingestion pipelines, or export Fragments directly from your app respecting its schema.
  • Deploy at scale with That Open Platform when you need enterprise operations.
See examples

Questions

Is Fragments tied to IFC?

No. Fragments is schema-agnostic: it can hold any data model, IFC included. You can keep IFC inside Fragments to preserve its semantics and gain performance, or export Fragments straight from your own app with your own schema, with no forced translation.

Can I edit geometry and data?

Yes, natively. Fragments is built to be written to, not only read: you can update geometry and properties in place, without a round trip through a text format.

How does it handle large models?

It is binary, compact and deduplicated, and it streams. Models load progressively, by fragment and on demand, with instancing for repeated elements and heavy work kept off the main thread. A huge model opens without waiting for everything to load.

What's the license?

MIT, like the rest of our open source. Free for commercial use, no fees, and no obligation to open-source your own app.