Claims and evidence
- Announced Primary source[1]page date
- Released Date unknownThe announcement says Grok-1.5 would reach early testers and existing Grok users on X in the coming days; no xAI page gives the rollout date. Evidence incompleteNo source
- Status Status unknownxAI has published no deprecation or retirement notice for Grok-1.5. The Grok-2 announcement of 2024-08-13 calls it xAI's previous model. Evidence incompleteNo source
- Change · Context length Context window raised to 128,000 tokens from 8,192; xAI says this is up to 16 times the previous length.Compared with Grok-1 Primary source[1]Long Context Understanding [2]Model details
- Change · Reasoning xAI reports better reasoning and problem solving, most notably in coding and maths.Compared with Grok-1 Primary source[1]
- Feature Long context Primary source[1]Long Context Understanding
- Context window 128,000 tokens tokens Primary source[1]subtitle; Long Context Understanding
- Parameters Not disclosedNot disclosed by xAI. No claim madeNo source
- Access consumer appAnnounced for early testers and existing Grok users on the X platform. Primary source[1]first paragraph; Looking Ahead
Lineage
Predecessors
- Grok-1 · November 2023
Successors
- Grok-2 · 13 August 2024
Based on
Not derived from another model.
Variants and derived
- Grok-1.5V · 12 April 2024 · variant
Siblings
None recorded.
All ancestors
- Grok-1 · November 2023
All descendants
- Grok-1.5V · 12 April 2024
- Grok-2 · 13 August 2024
- Grok-2 (December 2024 revision) · 12 December 2024
- Grok 3 · 19 February 2025
- Grok 4 · 9 July 2025
- Grok 4.1 · 17 November 2025
- Grok 4.20 · 17 February 2026
- Grok 4.3 · 17 April 2026
- Grok 4.5 · 16 July 2026
- Grok 4.6 · 12 August 2026
- Grok 4.7 · 21 September 2026
Variants
No variants recorded in this record.
Related AI Radar coverage
AI Radar coverage starts in June 2026; no coverage linked yet.