+
+
+
+
+
+
+
+
VS
VS
VS
VS
VS
VS
Grok-1.5 vs Grok-4 Heavy
Comprehensive side-by-side LLM comparison
Grok-4 Heavy leads with 52.5% higher average benchmark score. Grok-4 Heavy supports multimodal inputs. Overall, Grok-4 Heavy is the stronger choice for coding tasks.
+
+
+
+
xAI
Grok 1.5 was developed by xAI as an advanced language model, designed to provide helpful and accurate information with a focus on reasoning and factual knowledge. Built to serve as a conversational AI with strong analytical capabilities, it represents xAI's early generation of foundation models.
+
+
+
+
xAI
Grok 4 Heavy was created as a larger, more capable variant of Grok 4, designed to provide maximum reasoning depth and analytical capability. Built for the most demanding applications requiring sophisticated problem-solving, it represents xAI's flagship offering in the fourth generation.
1 year newer
Grok-1.5
xAI
2024-03-28
Grok-4 Heavy
xAI
2025-07-09
+
+
+
+
+
+
+
+
+
+
+
+
Average performance across 1 common benchmarks
+
+
+
+
Grok-1.5
Average Score:35.9%
+
+
+
+
Grok-4 Heavy
Average Score:88.4%(+52.5%)
+
+
+
+
Knowledge Cutoff
Training data recency comparison
Grok-4 Heavy
2024-12-31
More recent knowledge cutoff means awareness of newer technologies and frameworks
Provider Availability & Performance
Available providers and their performance metrics
+
+
+
+
Grok-1.5
0 providers
+
+
+
+
Grok-4 Heavy
0 providers
+
+
+
+
Grok-1.5
Avg Score:35.9%
Providers:0
+
+
+
+
Grok-4 Heavy
Avg Score:88.4%(+52.5%)
Providers:0