Grok Code Fast 1vsGLM-5.1
Grok Code Fast 1 | GLM-5.1 | |
|---|---|---|
| Specifications | ||
Parameters | — | 744B |
Context window | — | 200k |
| Benchmarks | ||
Nonsense detection BullshitBench v2Given a confidently-worded but nonsensical prompt, does the AI spot that it makes no sense and push back — instead of playing along and inventing an answer? The score is how often it clearly called out the nonsense. Higher is better. | — | 22% |
Next.js coding Next.js EvalsVercel's open eval of how well AI coding agents build and migrate real Next.js apps — measured as the share of tasks the agent completes successfully. Higher is better. | — | 75% |
Agentic terminal coding Terminal-Bench 2.0Can the AI work in a command-line terminal — running commands and finishing technical setup tasks the way a developer would? (Version 2.0 of the test.) Higher is better. | — | 63.5% |
Web browsing BrowseCompCan the AI browse the web and track down hard-to-find answers? Higher is better. | — | 68% |
Multidisciplinary reasoning Humanity's Last Exam · with toolsHumanity's Last Exam — extremely hard expert questions across many subjects. “With tools” means the AI is allowed to search the web or run code while answering. Higher is better. | — | 52.3% |
Science GPQA DiamondGraduate-level science questions in biology, physics, and chemistry — hard enough that subject-matter PhDs score around 65%. Higher is better. | — | 86.2% |
Community preference (code) Arena Elo (Code)Like the text arena, but people vote on which AI writes better code. The votes become a chess-style Elo rating on arena.ai. Higher is better. | 1163 | 1518Best |
| Overview | ||
| Company | SpaceXAI | Z.ai |
| Release date | Aug 28 2025 | Apr 7 2026 |
| Access | Proprietary | Open Weight |
Which is better: Grok Code Fast 1 or GLM-5.1?
GLM-5.1 leads Grok Code Fast 1 on 1 of the 1 benchmark they both report (Arena Elo (Code)). Grok Code Fast 1 shipped 222 days before GLM-5.1, so benchmark comparisons should account for the intervening progress.
Grok Code Fast 1 is proprietary, while GLM-5.1 is open weight.
On Arena Elo (Code), GLM-5.1 leads at 1518 vs Grok Code Fast 1 at 1163.
Frequently asked questions
Grok Code Fast 1 was released by SpaceXAI on Aug 28 2025.
GLM-5.1 was released by Z.ai on Apr 7 2026.
Grok Code Fast 1 is a proprietary model released by SpaceXAI. GLM-5.1 is an open weight model released by Z.ai.
Other comparisons
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