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GLM-5.1 vs GPT-5

GLM-5.1 leads the LLM Stats Score 39.2 to 33.8. GLM-5.1 is 2.1x cheaper per token.

Zhipu AI · OpenAI · Updated for 2026

Which is better?

GLM-5.1 leads the overall LLM Stats Score 39.2 to 33.8, ranking #62 overall.

In the 4 individual benchmarks reported for both models, GLM-5.1 wins 4; this is a narrower head-to-head signal than the composite indexes.

On price, GLM-5.1 is roughly 2.1x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

GPT-5 also accepts a larger context window (400,000 input tokens), making it the stronger choice for long documents and large codebases.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose GLM-5.1

  • overall performance matters — it scores 39.2 and ranks #62 on LLM Stats
  • your work emphasizes reasoning — it leads those capability indexes
  • you value its reported benchmark strengths — it wins 4 of 4 exact shared results
  • cost matters — it's about 2.1x cheaper per token
  • you want the most recent training data — it shipped Apr 2026
  • you need open weights you can self-host or fine-tune

Choose GPT-5

  • you process long inputs — it offers a 400,000 token context window

At a glance

The differences that matter most.

Core performance indexes
39.2
#62
33.8
#100
38.9
#61
34.2
#94
30.5
#53
26.4
#67
24.1
#57
9.1
#131
Cost, coverage & limits
Benchmark wins
4 of 4
0 of 4
Input price
$1.05 / M
$1.25 / M
Output price
$3.50 / M
$10.00 / M
Context window
202,752
400,000

Capability indexes

Additional strengths measured across groups of related public benchmarks

2 shared
Index
GLM-5.1
GPT-5
33.1#54
31.5#65
19.1#61
16.2#81
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

18 reported for GLM-5.1 · 34 for GPT-5

4 shared

GLM-5.1 outperforms in 4 benchmarks (BrowseComp, GPQA, HMMT 2025, Humanity's Last Exam), while GPT-5 is better at 0 benchmarks.

GLM-5.1 significantly outperforms across most benchmarks.

Tue Sep 22 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

GLM-5.1 costs less

For input processing, GLM-5.1 ($1.05/1M tokens) is 1.2x cheaper than GPT-5 ($1.25/1M tokens).

For output processing, GLM-5.1 ($3.50/1M tokens) is 2.9x cheaper than GPT-5 ($10.00/1M tokens).

In conclusion, GPT-5 is more expensive than GLM-5.1.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Tue Sep 22 2026 • llm-stats.com
Zhipu AI
GLM-5.1
Input tokens$1.05
Output tokens$3.50
Best providerDeepinfra
OpenAI
GPT-5
Input tokens$1.25
Output tokens$10.00
Best providerOpenAI
Notice missing or incorrect data?Start an Issue

Context Window

Maximum input and output token capacity

GPT-5 accepts 400,000 input tokens compared to GLM-5.1's 202,752 tokens. GLM-5.1 can generate longer responses up to 202,752 tokens, while GPT-5 is limited to 128,000 tokens.

Zhipu AI
GLM-5.1
Input202,752 tokens
Output202,752 tokens
OpenAI
GPT-5
Input400,000 tokens
Output128,000 tokens
Tue Sep 22 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

GPT-5 supports multimodal inputs, whereas GLM-5.1 does not.

GPT-5 can handle both text and other forms of data like images, making it suitable for multimodal applications.

GLM-5.1

Text
Images
Audio
Video

GPT-5

Text
Images
Audio
Video

License

Usage and distribution terms

GLM-5.1 is licensed under MIT, while GPT-5 uses a proprietary license.

License differences may affect how you can use these models in commercial or open-source projects.

GLM-5.1

MIT

Open weights

GPT-5

Proprietary

Closed source

Release Timeline

When each model was launched

GLM-5.1 was released on 2026-04-07, while GPT-5 was released on 2025-08-07.

GLM-5.1 is 8 months newer than GPT-5.

GLM-5.1

Apr 7, 2026

5 months ago

8mo newer
GPT-5

Aug 7, 2025

1.1 years ago

Knowledge Cutoff

When training data ends

GPT-5 has a documented knowledge cutoff of 2024-09-30, while GLM-5.1's cutoff date is not specified.

We can confirm GPT-5's training data extends to 2024-09-30, but cannot make a direct comparison without GLM-5.1's cutoff date.

GLM-5.1

GPT-5

Sep 2024

Provider Availability

GLM-5.1 is available from DeepInfra, FriendliAI, ZAI. GPT-5 is available from OpenAI.

GLM-5.1

deepinfra logo
Deepinfra
Input Price:Input: $1.05/1MOutput Price:Output: $3.50/1M
friendli logo
FriendliAI
Input Price:Input: $1.40/1MOutput Price:Output: $4.40/1M
z logo
Unknown Organization
Input Price:Input: $1.40/1MOutput Price:Output: $4.40/1M

GPT-5

openai logo
OpenAI
Input Price:Input: $1.25/1MOutput Price:Output: $10.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion

Judge for yourself.

Run your own prompts against GLM-5.1 and GPT-5 side-by-side, then vote on the output you prefer.

GLM-5.1
✓ Preferred
GPT-5
Open in Playground

FAQ

Common questions about GLM-5.1 vs GPT-5.

Which is better, GLM-5.1 or GPT-5?

GLM-5.1 leads the LLM Stats Score 39.2 to 33.8. GLM-5.1 is made by Zhipu AI and GPT-5 is made by OpenAI. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does GLM-5.1 compare to GPT-5 in benchmarks?

GLM-5.1 scores Vending-Bench 2: 100.0%, AIME 2026: 95.3%, HMMT 2025: 94.0%, GPQA: 86.2%, IMO-AnswerBench: 83.8%. GPT-5 scores SWE-Lancer (IC-Diamond subset): 100.0%, COLLIE: 99.0%, Tau2 Telecom: 96.7%, OpenAI-MRCR: 2 needle 128k: 95.2%, AIME 2025: 94.6%.

Is GLM-5.1 cheaper than GPT-5?

GLM-5.1 is 1.2x cheaper for input tokens. GLM-5.1 costs $1.05/M input and $3.50/M output via deepinfra. GPT-5 costs $1.25/M input and $10.00/M output via openai.

What are the context window sizes for GLM-5.1 and GPT-5?

GLM-5.1 supports 203K tokens and GPT-5 supports 400K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between GLM-5.1 and GPT-5?

Key differences include LLM Stats Score (39.2 vs 33.8), context window (203K vs 400K), input pricing ($1.05 vs $1.25/M), multimodal support (no vs yes), licensing (MIT vs Proprietary). See the full comparison above for benchmark-by-benchmark results.

Who makes GLM-5.1 and GPT-5?

GLM-5.1 is developed by Zhipu AI and GPT-5 is developed by OpenAI.