Chai-1
Multi-modal structure prediction for proteins, ligands, nucleic acids and glycans.
Developer: Chai Discovery
Overview
- Developer
- Chai Discovery
- Category
- Structure and complex prediction
- Commercial rights
- Commercial OK
- Commercial cost
- Free commercially
- Compute
- Single GPU
- Open weights
- Yes
- Last verified
Capabilities
Structure prediction for proteins with ligands, nucleic acids, glycans and modified residues. Input: FASTA plus optional restraints/MSAs; output: all-atom predicted complex with per-atom confidence - usable as an AlphaFold3 substitute whose weights are usable commercially.
When to use it
Good second opinion alongside Boltz-2 for complexes; easy pip install. Like all co-folding models it is unreliable for de novo binder interfaces it has not seen.
Input / Output
- Input
- FASTA plus optional restraints/MSAs
- Output
- all-atom predicted complex with per-atom confidence - usable as an AlphaFold3 substitute whose weights are usable commercially
Compute
Single GPU. Other tools with this compute profile →
Commercial Licensing
Commercial rights — may a company use it?
Commercial use OKLicence as writtenApache License 2.0
LICENSE file is Apache-2.0 and the README's Licence section states both code and model weights are Apache-2.0 and usable for academic and commercial purposes including drug discovery.
The licence read at the source allows use by a company. Attribution or copyleft conditions may still apply — read the note.
Commercial cost — is commercial use free of charge?
Free for commercial useFree to download and run commercially under Apache-2.0. Chai's hosted web platform is a separate product with its own terms; the open weights are what carry the free commercial grant.
Price and rights are separate: this panel is about money, the panel above is about permission.
- Commercial OK ≠ Free of charge. A tool can be licensed for company use and still need a paid licence for a dependency (BindCraft → PyRosetta).
- Free download ≠ Commercially licensed. Weights you can download at no cost may still forbid commercial use (AlphaFold 3).
- Unverified ≠ Commercially permitted. If no published statement settles it, treat it as unknown — not as a yes.
- Every component counts. Each status considers the code licence, the model-weights terms, required dependencies and any terms of use.
Model Weights
Open weights. A separate weights licence is Not documented as its own field; where weights carry different terms from the code, that is stated in the licence explanation above.
Dependencies
Not documented as a separate field. Any dependency that affects commercial use (for example a paid PyRosetta licence) is named in the licence and cost explanations above.
Official References
- Official site / repo
- github.com/chaidiscovery/chai-lab
From the makers of FoldScout
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Get told when a licence changes
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