Claude Fable 5 vs GLM-5.3
Claude Fable 5 shows notably better performance in the majority of benchmarks. GLM-5.3 is 9.3x cheaper per token.
Anthropic · Zhipu AI · Updated for 2026
Which is better?
Claude Fable 5 outperforms in 4 benchmarks (DeepSWE 1.1, ExploitBench, FrontierSWE, Humanity's Last Exam), while GLM-5.3 is better at 2 benchmarks (AutomationBench, Terminal-Bench 2.1). Claude Fable 5 shows notably better performance in the majority of benchmarks.
On price, GLM-5.3 is roughly 9.3x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
Based on current benchmark, pricing, and model metadata for 2026.
Choose Claude Fable 5
- you want the strongest raw capability — it leads on 4 of 6 shared benchmarks
Choose GLM-5.3
- cost matters — it's about 9.3x cheaper per token
- you want the most recent training data — it shipped Aug 2026
At a glance
The differences that matter most.
Performance Benchmarks
Comparative analysis across standard metrics
Claude Fable 5 outperforms in 4 benchmarks (DeepSWE 1.1, ExploitBench, FrontierSWE, Humanity's Last Exam), while GLM-5.3 is better at 2 benchmarks (AutomationBench, Terminal-Bench 2.1).
Claude Fable 5 shows notably better performance in the majority of benchmarks.
Arena Performance
Playground indexes and blind preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, Claude Fable 5 ($10.00/1M tokens) is 7.1x more expensive than GLM-5.3 ($1.40/1M tokens).
For output processing, Claude Fable 5 ($50.00/1M tokens) is 11.4x more expensive than GLM-5.3 ($4.40/1M tokens).
In conclusion, Claude Fable 5 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
Both models have the same input context window of 1,000,000 tokens. Both models can generate responses up to 128,000 tokens.
Input Capabilities
Supported data types and modalities
Claude Fable 5 supports multimodal inputs, whereas GLM-5.3 does not.
Claude Fable 5 can handle both text and other forms of data like images, making it suitable for multimodal applications.
Claude Fable 5
GLM-5.3
Release Timeline
When each model was launched
Claude Fable 5 was released on 2026-06-09, while GLM-5.3 was released on 2026-08-14.
GLM-5.3 is 2 months newer than Claude Fable 5.
Jun 9, 2026
2 months ago
Aug 14, 2026
1 weeks ago
2mo newerKnowledge Cutoff
When training data ends
Neither model specifies a knowledge cutoff date.
Unable to compare the recency of their training data.
Provider Availability
Claude Fable 5 is available from Anthropic. GLM-5.3 is available from ZAI.
Claude Fable 5
GLM-5.3
Outputs Comparison
Judge for yourself.
Run your own prompts against Claude Fable 5 and GLM-5.3 side-by-side, then vote on the output you prefer.
FAQ
Common questions about Claude Fable 5 vs GLM-5.3.