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Step 5 Preview
Grok 4.20 Beta 1
Grok 4.20 Beta 1 is a proprietary model from xAI. It ranks #65 of 351 on the LMArena text leaderboard with a rating of 1445.
- Developer
- xAI
- Released
- Feb 19, 2026
- Context window
- —
- Price in / out, per 1M tokens
- —
- Weights
- Proprietary
- Inputs
- —
- Reasoning
- —
- Tool use
- —
The rating LMArena published at each update since Feb 19, 2026. Ratings move as votes come in and new models join.
LMArena, by category
| Leaderboard | Rating | Rank | Votes |
|---|---|---|---|
| TextLMArena | 1445 | 65 / 351 | 27.9K |
| CodingLMArena | 1446 | 109 / 346 | 7.5K |
| MathLMArena | 1432 | 97 / 339 | 1.7K |
| Creative writingLMArena | 1438 | 48 / 349 | 4.2K |
| Instruction followingLMArena | 1415 | 96 / 351 | 8.8K |
| Hard promptsLMArena | 1441 | 94 / 351 | 17.5K |
| Multi-turnLMArena | 1451 | 66 / 349 | 4.6K |
| Long queriesLMArena | 1427 | 100 / 330 | 10.5K |
| ExpertLMArena | 1427 | 125 / 305 | 2.5K |
| Legal and governmentIndustries | 1434 | 104 / 325 | 2.1K |
| Medicine and healthcareIndustries | 1451 | 70 / 325 | 2K |
| Business and financeIndustries | 1425 | 94 / 344 | 5.4K |
| ChineseLanguages | 1476 | 82 / 328 | 1.7K |
| SpanishLanguages | 1439 | 85 / 249 | 951 |
| GermanLanguages | 1464 | 36 / 261 | 444 |
| FrenchLanguages | 1456 | 74 / 252 | 862 |
| JapaneseLanguages | 1449 | 33 / 236 | 226 |
LMArena, CC BY 4.0, as of Oct 22, 2026. Where a model is rated at several effort levels, its best is shown.
Compare Grok 4.20 Beta 1
xAI
The lab behind Grok, trained on one of the largest compute clusters and integrated with X. Founded 2023, based in San Francisco Bay Area. x.ai
Questions
Who makes Grok 4.20 Beta 1?
Grok 4.20 Beta 1 is made by xAI, founded 2023 and based in San Francisco Bay Area.
How does Grok 4.20 Beta 1 rank?
#65 of 351 on LMArena’s text leaderboard, rated 1445 (95% interval 1440–1449) from 27,914 votes, as of Oct 22, 2026.
Is Grok 4.20 Beta 1 open source?
No. Grok 4.20 Beta 1 is proprietary and served through its provider’s API.