That Open Company

free / open source (MIT and MPL-2.0) core libraries; a hosted "That Open Platform" and a paid custom-app development service exist alongside, with pricing not publicly disclosed for either Produce & Issue Documents

Open-source "AECOsystem" of JavaScript/TypeScript engine libraries (web-ifc, @thatopen/components, @thatopen/fragments, @thatopen/ui) for building browser-based, native-IFC BIM applications -- a WASM-speed IFC parser, a compact binary "Fragments" format for fast loading of huge models, and Three.js-based UI building blocks (viewers, clipping planes, measurement, DXF export) -- plus an emerging hosted "That Open Platform" (private beta) and a paid custom-BIM-app development service.

4.0 /5 composite score
Worth it (4.0/5) -- free, MIT/MPL-2.0 open-source IFC engine libraries (web-ifc: ~435K npm downloads/month) with an active 2025-2026 release cadence and full source-level access, though it is a developer SDK for building BIM apps rather than an end-user application, and the newer hosted platform layer is an opaque, gated private beta.
Worth it

Rubric Scorecard

How we grade →

Criterion Score Evidence
Value for the price 4/5 free / open source (MIT and MPL-2.0) core libraries; a hosted "That Open Platform" and a paid custom-app development service exist alongside, with pricing not publicly disclosed for either, from $0, free tier
Agent Friendliness 4/5 CLI, API: Full open-source TypeScript/JavaScript library API (web-ifc, @thatopen/components, @thatopen/fragments, @thatopen/ui); a separate thatopen CLI and API-token auth exist for the commercial, private-beta That Open Platform Source →
Ease of adoption 4/5 web-saas, moderate learning curve
Portability & lock-in 5/5 3 file formats, export: bulk Source →
Interoperability 3/5 1 integrations
Visit That Open Company →

How we verified this: we checked That Open Company against its live site and an independent source — github.com. Nothing on this page is listed from memory. See how we grade. Verified 2026-07-03.

Evidence

File formats

FormatDirectionSupport
IFC2X3 both full
IFC4 both full
DXF export partial

Integrations

Three.js (native)

Adoption

Deploymentweb-saas
Self-serve signupyes
Implementation requirednone
SSO/admin requiredno
Training requiredtutorials
Learning curvemoderate

Data export

Export mechanismbulk
Export scopeall-data

Ecosystem

Plugin marketplaceno

Pricing detail

Free tier scopeusable

Also covers

That Open Company also appears in these sub-categories:

BIM Coordination & Clash Detection
Its Fragments format and Three.js-based components (clipping planes, measurement, floorplan navigation) are the standard open building blocks behind several independent web-based IFC viewers and coordination tools.

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