The AI Museum
AI Analytics1,072 recordsRecounted 23 September 2026

Open-weight models in 2021

Weightsopenclosedunknownfrontier only
Year20262025202420232022202120202019201820172016
2 filters active, showing 41 of 1,072 recordsClear all

41

Models

25 organisations

100%

Open weights

41 open, 0 closed

1

Frontier

By Epoch's flag

1.6T

Largest traceable

Switch

2021

Span

29 with a traceable size

Releases

by month
Jan
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Apr
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Organisation

Country

Domain

Records

41
Open-weight models in 2021, newest first. Each row links to the source Epoch AI records for it.
ModelOrganisationReleasedParametersWeights
ContrieverMeta AI2021-12110M *Open
LDM-1.45BHeidelberg University2021-121BOpen
LongT5Google Research2021-123BOpen
XGLM-7.5BMeta AI2021-128BOpen
CodeT5-baseSalesforce2021-11220M *Open
Masked Autoencoders ViT-HFacebook AI Research2021-11632M *Open
Projected GANHeidelberg University2021-11—Open
Swin Transformer V2 (SwinV2-G)Microsoft Research Asia2021-113BOpen
AlphaFold-MultimerGoogle DeepMind2021-10—Open
base LM+GNN+kNNShannon.AI2021-10274MOpen
S4Stanford University2021-10249M *Open
PLATO-XLBaidu2021-0911BOpen
TrOCRBeihang University2021-09558MOpen
6-Act TetherFacebook AI Research2021-085MOpen
DNABERTNortheastern University2021-08110MOpen
XLMR-XXLFacebook AI Research2021-0811BOpen
YOLOX-XMegvii Inc2021-0899M *Open
Zidong TaichuChinese Academy of Sciences2021-083BOpen
ERNIE 3.0Baidu2021-0710BOpen
HuBERTFacebook AI Research2021-071B *Open
SEERFacebook AI Research2021-071BOpen
DeBERTaMicrosoft2021-062BOpen
Denoising Diffusion Probabilistic Models (LSUN Bedroom)University of California (UC) Berkeley2021-06256MOpen
EfficientNetV2-XLGoogle2021-06208MOpen
EMDRMila - Quebec AI (originally Montreal Institute for Learning Algorithms)2021-06440MOpen
StyleGAN3-RNVIDIA2021-062MOpen
StyleGAN3-TNVIDIA2021-062MOpen
ADMOpenAI2021-05559MOpen
ByT5-XXLGoogle2021-0513B *Open
CogViewTsinghua University2021-054B *Open
ProtBERT-BFDTechnical University of Munich2021-05420MOpen
ProtT5-XL-U50Technical University of Munich2021-053BOpen
Transformer local-attention (NesT-B)Google Cloud2021-0590MOpen
Generative BSTFacebook AI Research2021-039BOpen
UnicornAllen Institute for AI2021-0311BOpen
MSA TransformerFacebook AI Research2021-02100M *Open
SRU++ LargeASAPP2021-02234MOpen
CLIP (ResNet-50)OpenAI2021-0189M *Open
CLIP (ViT L/14@336px)OpenAI2021-01370MOpen
DeiT-BMeta AI2021-0186MOpen
SwitchGoogle2021-011.6TOpen

An asterisk marks a parameter figure the source does not consider traceable to the people who built the model. That judgement is the source’s and it has false negatives: Kimi K3 is marked speculative at 2.8T while Moonshot’s own model card states the figure. Why that distinction carries the whole exhibit.

Counts are of models Epoch AI records as notable, not of every model released. The most recent month is always incomplete, because a model enters the dataset when it is reviewed rather than when it ships.

Epoch AI, 'Data on AI Models'. Published online at epoch.ai. Retrieved from 'https://epoch.ai/data/ai-models-documentation' Used under CC BY 4.0.

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