Claude Mythos 5.1 vs GLM-5.3
Claude Mythos 5.1 and GLM-5.3 are closely matched at 44.5 and 52.1 on the LLM Stats Score. GLM-5.3 is 10.5x cheaper per token.
Anthropic · Zhipu AI · Updated for 2026
Which is better?
Claude Mythos 5.1 and GLM-5.3 are closely matched on the overall LLM Stats Score at 44.5 and 52.1.
In the 1 individual benchmarks reported for both models, Claude Mythos 5.1 wins 1; this is a narrower head-to-head signal than the composite indexes.
On price, GLM-5.3 is roughly 10.5x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
GLM-5.3 also accepts a larger context window (1,048,576 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 Claude Mythos 5.1
- you value its reported benchmark strengths — it wins 1 of 1 exact shared results
- you want the most recent training data — it shipped Sep 2026
Choose GLM-5.3
- cost matters — it's about 10.5x cheaper per token
- you process long inputs — it offers a 1,048,576 token context window
- you need open weights you can self-host or fine-tune
At a glance
The differences that matter most.
Individual benchmarks
1 reported for Claude Mythos 5.1 · 17 for GLM-5.3
Claude Mythos 5.1 outperforms in 1 benchmarks (Terminal-Bench 4.0), while GLM-5.3 is better at 0 benchmarks.
Claude Mythos 5.1 significantly outperforms across most benchmarks.
Human preference
Blind head-to-head votes and playground preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, Claude Mythos 5.1 ($10.00/1M tokens) is 8.3x more expensive than GLM-5.3 ($1.20/1M tokens).
For output processing, Claude Mythos 5.1 ($50.00/1M tokens) is 12.5x more expensive than GLM-5.3 ($4.00/1M tokens).
In conclusion, Claude Mythos 5.1 is more expensive than GLM-5.3.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
GLM-5.3 accepts 1,048,576 input tokens compared to Claude Mythos 5.1's 1,000,000 tokens. GLM-5.3 can generate longer responses up to 1,048,576 tokens, while Claude Mythos 5.1 is limited to 128,000 tokens.
Input capabilities
Documented input modalities across available providers
Claude Mythos 5.1 supports multimodal inputs, whereas GLM-5.3 does not.
Claude Mythos 5.1 can handle both text and other forms of data like images, making it suitable for multimodal applications.
Claude Mythos 5.1
GLM-5.3
License
Usage and distribution terms
Claude Mythos 5.1 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.
Proprietary
Closed source
GLM-5.3 License
Open weights
Release Timeline
When each model was launched
Claude Mythos 5.1 was released on 2026-09-01, while GLM-5.3 was released on 2026-08-14.
Claude Mythos 5.1 is 1 month newer than GLM-5.3.
Sep 1, 2026
3 weeks ago
2w newerAug 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.
Provider Availability
Claude Mythos 5.1 is available from Anthropic. GLM-5.3 is available from DeepInfra, FriendliAI, Novita, ZAI.
Claude Mythos 5.1
GLM-5.3
Outputs Comparison
Judge for yourself.
Run your own prompts against Claude Mythos 5.1 and GLM-5.3 side-by-side, then vote on the output you prefer.
FAQ
Common questions about Claude Mythos 5.1 vs GLM-5.3.