Grok-1.5
xAI's 128K-context upgrade with sharper math and coding reasoning.
About
Grok-1.5 was announced by xAI on March 28, 2024, as the successor to Grok-1, bringing improved reasoning and a 128,000-token context window, 16 times larger than its predecessor. Benchmarks published by xAI showed large gains over Grok-1 in math and coding: 50.6% on MATH, 90% on GSM8K, and 74.1% on HumanEval, with perfect retrieval on Needle-in-a-Haystack evaluations up to 128K tokens.
Shortly after came Grok-1.5V, xAI's first multimodal model, adding vision encoders so the same backbone could process documents, diagrams, charts, and photographs. Unlike Grok-1, whose weights were open-sourced, Grok-1.5 remained closed and available only through X's Grok chatbot.
Specs
Context window
Pricing
Free quota
API access
Weights
Released
Benchmarks
Provider-reported unless a source says otherwise. Benchmarks are marketing-adjacent by nature — treat them as directional.
Use cases
Trust score — 7/10
Scored 7/10 (metrics tier, metrics-v1). Evidence: Verified via vendor site/docs/GitHub and reputable coverage, wave 75; Trending score 72/100 from researcher assessment.