GLM-4.5 vs Grok 4 Fast: Specs & Benchmark Comparison

CharacteristicGLM-4.5Grok 4 Fast
CompanyZhipu AIxAI
Release DateJuly 27, 2025August 27, 2025
Parameters355B
MultimodalNoYes
Context (input)131K2.0M
Context (output)98K30K
Input Price / 1M$0.60$0.20
Output Price / 1M$2.20$0.50
Average Score0.80.8
Benchmarks
LiveCodeBench0.70.8
GPQA0.80.9

Visual Benchmark Comparison

GLM-4.5
Grok 4 Fast
LiveCodeBench0.7 vs 0.8
0.7
0.8
GPQA0.8 vs 0.9
0.8
0.9

Verdict

Grok 4 Fast leads in 3 out of 4 comparison categories.

Overall Performance

Both models show comparable average scores: GLM-4.5 — 0.8, Grok 4 Fast — 0.8.

API Cost

Grok 4 Fast is 4.0x cheaper: input $0.20/1M vs $0.60/1M tokens.

Context Window

Grok 4 Fast supports a larger context: 2M vs 131K tokens.

Recency

Grok 4 Fast is newer: released 8/27/2025 vs 7/27/2025.

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Frequently Asked Questions

Which is better for coding — GLM-4.5 or Grok 4 Fast?
Direct comparison on the SWE-Bench benchmark is not available. We recommend reviewing other metrics on the comparison page.
Which model is cheaper — GLM-4.5 or Grok 4 Fast?
Grok 4 Fast is cheaper for input: $0.20 per 1M tokens vs $0.60.
Which has a larger context window — GLM-4.5 or Grok 4 Fast?
Grok 4 Fast supports a larger context: 2,000,000 tokens vs 131,072.

The GLM-4.5 and Grok 4 Fast comparison is updated for 2026. Data includes benchmark results, API pricing, context window size and other specifications. For more detailed information, visit the GLM-4.5 or Grok 4 Fast page. See also the complete list of AI model comparisons.