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Independent
OpenAssistant Pythia 12B
OpenAssistant Pythia 12B is an open-weight model. It ranks #414 of 351 on the LMArena text leaderboard with a rating of 916.
LMArena text916
Rank#414/351
95% interval905–927
Votes6.3K
- Developer
- —
- Released
- Oct 20, 2026
- Context window
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- Price in / out, per 1M tokens
- —
- Weights
- Open · Apache 2.0
- Inputs
- —
- Reasoning
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- Tool use
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LMArena, by category
| Leaderboard | Rating | Rank | Votes |
|---|---|---|---|
| TextLMArena | 916 | 414 / 351 | 6.3K |
| CodingLMArena | 900 | 408 / 346 | 714 |
| MathLMArena | 892 | 400 / 339 | 687 |
| Creative writingLMArena | 923 | 411 / 349 | 1.1K |
| Instruction followingLMArena | 887 | 413 / 351 | 1.7K |
| Hard promptsLMArena | 884 | 413 / 351 | 1.2K |
| Multi-turnLMArena | 869 | 411 / 349 | 683 |
| Legal and governmentIndustries | 922 | 388 / 325 | 266 |
| Medicine and healthcareIndustries | 819 | 389 / 325 | 201 |
| Business and financeIndustries | 822 | 408 / 344 | 454 |
| ChineseLanguages | 803 | 392 / 328 | 321 |
LMArena, CC BY 4.0, as of Oct 22, 2026. Where a model is rated at several effort levels, its best is shown.
Compare OpenAssistant Pythia 12B
Questions
How does OpenAssistant Pythia 12B rank?
#414 of 351 on LMArena’s text leaderboard, rated 916 (95% interval 905–927) from 6,310 votes, as of Oct 22, 2026.
Is OpenAssistant Pythia 12B open source?
OpenAssistant Pythia 12B has open weights under the Apache 2.0 license.