Claude Fable 5 vs Claude Opus 4.5
Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.
Claude Fable 5
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.
Claude Opus 4.5
Anthropic · Nov 2025
The November 2025 Opus that cut flagship pricing 3x to $5/$25 and was the first model past 80% on SWE-bench Verified.
The verdict
Claude Fable 5 wins 1 of the 1 benchmarks these models share, against 0 for Claude Opus 4.5. Claude Opus 4.5 is about 2.0x cheaper per blended million tokens (3:1 input:output mix). Claude Fable 5 also takes 1M of context versus 200K for Claude Opus 4.5.
Benchmark head-to-head 1–0
Specs & pricing
| Claude Fable 5 | Claude Opus 4.5 | |
|---|---|---|
| modhub Index | — | — |
| Input price / 1M | $10 | $5 |
| Output price / 1M | $50 | $25 |
| 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 | Mar 2025 |
| Released | Jun 2026 | Nov 2025 |
| Example monthly cost* | $175.00 | $87.50 |
* 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 Opus 4.5?
- Claude Fable 5 wins 1 of the 1 benchmarks these models share, against 0 for Claude Opus 4.5. Claude Opus 4.5 is about 2.0x cheaper per blended million tokens (3:1 input:output mix). Claude Fable 5 also takes 1M of context versus 200K for Claude Opus 4.5.
- Which is cheaper, Claude Fable 5 or Claude Opus 4.5?
- Claude Fable 5 costs $10/$50 per million input/output tokens, while Claude Opus 4.5 costs $5/$25. For a typical workload of 10M input and 1.5M output tokens per month, that's $175.00 versus $87.50.
- Which model is better for coding, Claude Fable 5 or Claude Opus 4.5?
- On SWE-bench Verified — the standard agentic-coding benchmark — Claude Fable 5 scores ~95% versus 80.9% for Claude Opus 4.5, making Claude Fable 5 the stronger pick for coding agents.
More comparisons
Claude Fable 5 vs GPT-5.5Claude Opus 4.5 vs GPT-5.5Claude Fable 5 vs GPT-5.2Claude Opus 4.5 vs GPT-5.2Claude Fable 5 vs GPT-5.1Claude Opus 4.5 vs GPT-5.1Claude Fable 5 vs GPT-5Claude Opus 4.5 vs GPT-5Claude Fable 5 vs GPT-5 miniClaude Opus 4.5 vs GPT-5 miniClaude Fable 5 vs OpenAI o3Claude Opus 4.5 vs OpenAI o3