The AI Museum
AI Analytics1,072 recordsRecounted 23 September 2026

Open-weight frontier models from United States of America

10

Models

6 organisations

100%

Open weights

10 open, 0 closed

10

Frontier

By Epoch's flag

1.6T

Largest traceable

Switch

2018–2024

Span

10 with a traceable size

Records

10
Open-weight frontier models from United States of America, newest first. Each row links to the source Epoch AI records for it.
ModelOrganisationReleasedParametersWeights
Llama 3.1-405BMeta AI2024-07405BOpen
Nemotron-4 340BNVIDIA2024-06340BOpen
SwitchGoogle2021-011.6TOpen
mT5-XXLGoogle2020-1013BOpen
XLM-RoBERTaFacebook AI2019-11550MOpen
T5-11BGoogle2019-1011BOpen
T5-3BGoogle2019-103BOpen
RoBERTa LargeFacebook2019-07355MOpen
XLNetCarnegie Mellon University (CMU)2019-06340MOpen
ResNeXt-101 32x48dFacebook2018-05829MOpen

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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