GLM-4.6 vs GPT-5.1
GPT-5.1 significantly outperforms across most benchmarks. GLM-4.6 is 3.8x cheaper per token.
Zhipu AI · OpenAI · Updated for 2026
Which is better?
GLM-4.6 outperforms in 0 benchmarks, while GPT-5.1 is better at 3 benchmarks (AIME 2025, GPQA, SWE-Bench Verified). GPT-5.1 significantly outperforms across most benchmarks.
On price, GLM-4.6 is roughly 3.8x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
GPT-5.1 also accepts a larger context window (400,000 input tokens), making it the stronger choice for long documents and large codebases.
Based on current benchmark, pricing, and model metadata for 2026.
Choose GLM-4.6
- cost matters — it's about 3.8x cheaper per token
- you need open weights you can self-host or fine-tune
Choose GPT-5.1
- you want the strongest raw capability — it leads on 3 of 3 shared benchmarks
- you process long inputs — it offers a 400,000 token context window
- you want the most recent training data — it shipped Nov 2025
At a glance
The differences that matter most.
Performance Benchmarks
Comparative analysis across standard metrics
GLM-4.6 outperforms in 0 benchmarks, while GPT-5.1 is better at 3 benchmarks (AIME 2025, GPQA, SWE-Bench Verified).
GPT-5.1 significantly outperforms across most benchmarks.
Arena Performance
Playground indexes and blind preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, GLM-4.6 ($0.55/1M tokens) is 2.3x cheaper than GPT-5.1 ($1.25/1M tokens).
For output processing, GLM-4.6 ($2.00/1M tokens) is 5.0x cheaper than GPT-5.1 ($10.00/1M tokens).
In conclusion, GPT-5.1 is more expensive than GLM-4.6.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
GPT-5.1 accepts 400,000 input tokens compared to GLM-4.6's 131,072 tokens. GLM-4.6 can generate longer responses up to 131,072 tokens, while GPT-5.1 is limited to 128,000 tokens.
Input Capabilities
Supported data types and modalities
Both GLM-4.6 and GPT-5.1 support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
GLM-4.6
GPT-5.1
License
Usage and distribution terms
GLM-4.6 is licensed under MIT, while GPT-5.1 uses a proprietary license.
License differences may affect how you can use these models in commercial or open-source projects.
MIT
Open weights
Proprietary
Closed source
Release Timeline
When each model was launched
GLM-4.6 was released on 2025-09-30, while GPT-5.1 was released on 2025-11-13.
GPT-5.1 is 1 month newer than GLM-4.6.
Sep 30, 2025
10 months ago
Nov 13, 2025
9 months ago
1mo newerKnowledge Cutoff
When training data ends
GPT-5.1 has a documented knowledge cutoff of 2024-09-30, while GLM-4.6's cutoff date is not specified.
We can confirm GPT-5.1's training data extends to 2024-09-30, but cannot make a direct comparison without GLM-4.6's cutoff date.
—
Sep 2024
Provider Availability
GLM-4.6 is available from Fireworks, DeepInfra. GPT-5.1 is available from OpenAI.
GLM-4.6
GPT-5.1
Outputs Comparison
Judge for yourself.
Run your own prompts against GLM-4.6 and GPT-5.1 side-by-side, then vote on the output you prefer.
FAQ
Common questions about GLM-4.6 vs GPT-5.1.