Claude Fable 5 vs Grok 4.20
How do these models stack up? Below is an expert side-by-side comparison of specifications, context window capacity, live pricing per million tokens, and standardized benchmark scores for Claude Fable 5 and Grok 4.20.
Claude Fable 5
Claude Fable 5 is a Mythos-class model from Anthropic, built for autonomous knowledge work and coding. It supports text, image, and file inputs with text output, with reasoning support and...
Grok 4.20
Grok 4.20 is a reasoning model from xAI with industry-leading speed and agentic tool calling capabilities. It combines the lowest hallucination rate on the market with strict prompt adherance, delivering...
Technical Specifications
| Specification | Claude Fable 5 | Grok 4.20 |
|---|---|---|
| Provider | Anthropic | xAI |
| Context Window | 1,000,000 tokens | 2,000,000 tokens |
| Agent Suitability | N/A | N/A |
| Time to First Token (TTFT) | N/A | N/A |
| Deployment Model | managed api | managed api |
| Production Stability | beta | beta |
| API Available | Yes | Yes |
| Released Date | 2026-06-09 | 2026-03-31 |
API Pricing Comparison
Input Price per Million Tokens
Claude Fable 5
$10.00
Grok 4.20
$1.25
Output Price per Million Tokens
Claude Fable 5
$50.00
Grok 4.20
$2.50
Want to test both models live?
Run side-by-side prompt prompts in our dynamic Sandbox. Check execution speeds, latency metrics, and compute actual costs in real-time.
Benchmark Performance Metrics
Scores show the raw performance percentages verified across key evaluation suites. Higher bars indicate superior accuracy and capability in that domain.
Claude Fable 5 Quirks & Gotchas
No developer gotchas reported.
Grok 4.20 Quirks & Gotchas
No developer gotchas reported.