Claude Fable 5 vs Claude Sonnet 4.5
Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.
Anthropic · Jun 2026
The first GA model of Anthropic's Mythos class — a tier above Opus — and the current SWE-bench Verified leader, at $10/$50 per 1M tokens.
Anthropic · Sep 2025
The model that made 30-hour autonomous coding sessions real — 77.2% SWE-bench Verified and a 1M-token context beta at $3/$15.
The verdict
Claude Fable 5 wins 1 of the 1 benchmarks these models share, against 0 for Claude Sonnet 4.5. On price the gap is dramatic: Claude Sonnet 4.5 works out roughly 3.3x cheaper per blended million tokens. Claude Fable 5 also takes 1M of context versus 200K for Claude Sonnet 4.5.
Benchmark head-to-head 1–0
Specs & pricing
| Claude Fable 5 | Claude Sonnet 4.5 | |
|---|---|---|
| modhub Index | — | 65.5 |
| Input price / 1M | $10 | $3 |
| Output price / 1M | $50 | $15 |
| Context window | 1M | 200K |
| Max output | 128K | 64K |
| Open weights | no | no |
| Reasoning model | yes | yes |
| Multimodal input | text, image | text, image |
| Knowledge cutoff | Jan 2026 | Jan 2025 |
| Released | Jun 2026 | Sep 2025 |
| Example monthly cost* | $175.00 | $52.50 |
* 10M input + 1.5M output tokens per month at list prices, no caching. Green = better value on that row.
Frequently asked questions
- Which is better, Claude Fable 5 or Claude Sonnet 4.5?
- Claude Fable 5 wins 1 of the 1 benchmarks these models share, against 0 for Claude Sonnet 4.5. On price the gap is dramatic: Claude Sonnet 4.5 works out roughly 3.3x cheaper per blended million tokens. Claude Fable 5 also takes 1M of context versus 200K for Claude Sonnet 4.5.
- Which is cheaper, Claude Fable 5 or Claude Sonnet 4.5?
- Claude Fable 5 costs $10/$50 per million input/output tokens, while Claude Sonnet 4.5 costs $3/$15. For a typical workload of 10M input and 1.5M output tokens per month, that's $175.00 versus $52.50.
- Which model is better for coding, Claude Fable 5 or Claude Sonnet 4.5?
- On SWE-bench Verified — the standard agentic-coding benchmark — Claude Fable 5 scores ~95% versus 77.2% for Claude Sonnet 4.5, making Claude Fable 5 the stronger pick for coding agents.