The AI arena is free today

Open Superagent

Claude Mythos Preview vs GLM-5.3

Claude Mythos Preview and GLM-5.3 are closely matched at 54.4 and 52.0 on the LLM Stats Score. GLM-5.3 is 26.3x cheaper per token.

Anthropic · Zhipu AI · Updated for 2026

Which is better?

Claude Mythos Preview and GLM-5.3 are closely matched on the overall LLM Stats Score at 54.4 and 52.0.

The models split the 2 individual benchmarks reported for both models evenly.

On price, GLM-5.3 is roughly 26.3x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

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

Choose Claude Mythos Preview

  • you want predictable pricing at $25.00/M input and $125.00/M output

Choose GLM-5.3

  • cost matters — it's about 26.3x cheaper per token
  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

Claude Mythos Preview
Anthropic
GLM-5.3
Zhipu AI
Core performance indexes
LLM Stats Score
54.4
#5
52.0
#12
Reasoning
55.3
#4
51.4
#7
Coding
43.9
#6
41.4
#9
Agents
36.0
#20
38.3
#10
Cost, coverage & limits
Benchmark wins
1 of 2
1 of 2
Input price
$25.00 / M
$1.20 / M
Output price
$125.00 / M
$4.00 / M
Context window
—
1,048,576

Capability indexes

Additional strengths measured across groups of related public benchmarks

1 shared
Index
Claude Mythos Preview
GLM-5.3
Safety
16.3#10
21.6#6
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

16 reported for Claude Mythos Preview · 17 for GLM-5.3

2 shared

Claude Mythos Preview outperforms in 1 benchmarks (Humanity's Last Exam), while GLM-5.3 is better at 1 benchmark (CyberGym).

Both models are evenly matched across the benchmarks.

Wed Oct 07 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

GLM-5.3 costs less

For input processing, Claude Mythos Preview ($25.00/1M tokens) is 20.8x more expensive than GLM-5.3 ($1.20/1M tokens).

For output processing, Claude Mythos Preview ($125.00/1M tokens) is 31.3x more expensive than GLM-5.3 ($4.00/1M tokens).

In conclusion, Claude Mythos Preview is more expensive than GLM-5.3.*

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

Lowest available price from all providers
Wed Oct 07 2026 • llm-stats.com
Anthropic
Claude Mythos Preview
Input tokens$25.00
Output tokens$125.00
Best providerAnthropic
Zhipu AI
GLM-5.3
Input tokens$1.20
Output tokens$4.00
Best providerDeepinfra
Notice missing or incorrect data?

Context Window

Maximum input and output token capacity

Only GLM-5.3 specifies input context (1,048,576 tokens). Only GLM-5.3 specifies output context (1,048,576 tokens).

Anthropic
Claude Mythos Preview
Input- tokens
Output- tokens
Zhipu AI
GLM-5.3
Input1,048,576 tokens
Output1,048,576 tokens
Wed Oct 07 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Claude Mythos Preview supports multimodal inputs, whereas GLM-5.3 does not.

Claude Mythos Preview can handle both text and other forms of data like images, making it suitable for multimodal applications.

Claude Mythos Preview

Text
Images
Audio
Video

GLM-5.3

Text
Images
Audio
Video

License

Usage and distribution terms

Claude Mythos Preview is licensed under a proprietary license, while GLM-5.3 uses GLM-5.3 License.

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

Claude Mythos Preview

Proprietary

Closed source

GLM-5.3

GLM-5.3 License

Open weights

Release Timeline

When each model was launched

GLM-5.3 was released on 2026-08-14, while Claude Mythos Preview's release date is not specified.

We can confirm GLM-5.3's release timeline, but cannot make a direct age comparison without Claude Mythos Preview's release date.

Claude Mythos Preview

—

GLM-5.3

Aug 14, 2026

1 months ago

Knowledge Cutoff

When training data ends

Neither model specifies a knowledge cutoff date.

Unable to compare the recency of their training data.

No cutoff dates available

Provider Availability

Claude Mythos Preview is available from Anthropic. GLM-5.3 is available from DeepInfra, FriendliAI, Novita, ZAI.

Claude Mythos Preview

anthropic logo
Anthropic
Input Price:Input: $25.00/1MOutput Price:Output: $125.00/1M

GLM-5.3

deepinfra logo
Deepinfra
Input Price:Input: $1.20/1MOutput Price:Output: $4.00/1M
friendli logo
FriendliAI
Input Price:Input: $1.40/1MOutput Price:Output: $4.40/1M
novita logo
Novita
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
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against Claude Mythos Preview and GLM-5.3 side-by-side, then vote on the output you prefer.

Claude Mythos Preview
✓ Preferred
GLM-5.3
Open in Playground

FAQ

Common questions about Claude Mythos Preview vs GLM-5.3.

Which is better, Claude Mythos Preview or GLM-5.3?

Claude Mythos Preview and GLM-5.3 are closely matched on the LLM Stats Score at 54.4 and 52.0. Claude Mythos Preview is made by Anthropic and GLM-5.3 is made by Zhipu AI. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Claude Mythos Preview compare to GLM-5.3 in benchmarks?

Claude Mythos Preview scores CyBench: 100.0%, USAMO25: 97.6%, GPQA: 94.6%, SWE-Bench Verified: 93.9%, CharXiv-R: 93.2%. GLM-5.3 scores Terminal-Bench 2.1: 88.2%, CyberGym: 84.5%, FrontierSWE: 78.1%, Toolathlon: 73.0%, DeepSWE 1.1: 66.9%.

Is Claude Mythos Preview cheaper than GLM-5.3?

GLM-5.3 is 20.8x cheaper for input tokens. Claude Mythos Preview costs $25.00/M input and $125.00/M output via anthropic. GLM-5.3 costs $1.20/M input and $4.00/M output via deepinfra.

What are the context window sizes for Claude Mythos Preview and GLM-5.3?

Claude Mythos Preview supports an unknown number of tokens and GLM-5.3 supports 1.0M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Claude Mythos Preview and GLM-5.3?

Key differences include LLM Stats Score (54.4 vs 52.0), input pricing ($25.00 vs $1.20/M), multimodal support (yes vs no), licensing (Proprietary vs GLM-5.3 License). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Mythos Preview and GLM-5.3?

Claude Mythos Preview is developed by Anthropic and GLM-5.3 is developed by Zhipu AI.

Related comparisons