Pricing (as of Sept 1, 2026 launch)
Verified against Anthropic's official pricing page (platform.claude.com). All prices in USD per 1M tokens.
| Tier | Input | 5m Cache Write | 1h Cache Write | Cache Read | Output | Notes |
|---|---|---|---|---|---|---|
| Standard | $10.00 | $12.50 | $20.00 | $0.25 | $50.00 | Standard rate. Flat 1M context |
Input, output, and cache writes are unchanged from Fable 5 ($10/$50, 5m writes $12.50, 1h writes $20).
Only cache reads dropped from $1.00 → $0.25 (a 75% cut) — now 2.5% of the base input price (vs 10% for other models).
* Anthropic estimates this yields ~25% lower cost on typical workloads and up to ~45% on highly agentic (tool- and context-heavy) workloads.
Primary sources: Anthropic announcement (Cost and availability) · platform.claude.com pricing (verified 2026-09-01). Batch API is 50% off (input $5 / output $25).
Model Specifications
Sources: Claude Platform model overview (verified 2026-09-01). All current models support text & image input, text output, multilingual, vision and tool use. Available on AWS Bedrock, Google Cloud (Vertex AI) and Microsoft Azure (Foundry).
Performance — a major leap over Fable 5
Benchmarks from Anthropic's announcement (evaluated with production safeguards enabled). Figures as published by each vendor.
| Benchmark | Fable 5.1 | Fable 5 | Claude Opus 5 | GPT-5.6 Sol |
|---|---|---|---|---|
| Agentic scientific research Terminal-Bench-Science 0.1 | 52.6% | 24.7% | 29.0% | 22.4% |
| Agentic coding Terminal-Bench 4.0 | 55.8% | 42.0% | 52.3% | 37.3% |
| Knowledge work GDPval-AA v2 | 1853 | 1723 | 1824 | 1711 |
| Computer use OSWorld 2.0 (partial) | 77.9% | 72.9% | 75.4% | — |
| Multidisciplinary reasoning Humanity's Last Exam (no tools) | 60.9% | 57.8% | 56.6% | — |
| Business workflows AutomationBench | 31.4% | 17.1% | 26.9% | 19.6% |
| Agentic coding CursorBench 3.2.0 | 73.4% | 70.5% | 70.0% | 67.2% |
Terminal-Bench-Science more than doubling Fable 5's score (24.7% → 52.6%) is the headline change — the area Anthropic centers in this launch. Mythos 5.1 hits 60.9% on Terminal-Bench 4.0. HLE (with tools) is 65.0%.
Source: Anthropic announcement (verified 2026-09-01)
Fable 5.1 vs Mythos 5.1
Claude Fable 5.1 — generally available to all users via the API, Claude.ai, Claude Code and Claude Cowork.
Claude Mythos 5.1 — trusted-access only. A version with relaxed safeguards in cybersecurity (CVP) and life sciences (LSVP) for vetted organizations. See the Mythos 5.1 page for details.
Competitor Flagship Price Comparison
All prices in USD per 1M tokens (standard rate). Cache-read handling is the key cost differentiator.
| Model | Provider | Input | Output | Cache Read | Notes |
|---|---|---|---|---|---|
| Claude Fable 5.1 | Anthropic | $10.00 | $50.00 | $0.25 | New flagship (Mythos-class) |
| Claude Opus 5 | Anthropic | $5.00 | $25.00 | $0.50 | For standard workloads. Half Fable 5.1's price |
| GPT-5.6 Sol | OpenAI | $4.00 | $20.00 | $0.40 | Promo (thru 2026-11-21). Cheapest in absolute terms |
| Claude Fable 5 | Anthropic | $10.00 | $50.00 | $1.00 | Previous gen. Fable 5.1 cuts only cache reads 75% |
💡 How to read it: Fable 5.1 is for the hardest, longest-horizon agents. For price-per-performance, GPT-5.6 Sol ($4/$20) or Claude Opus 5 ($5/$25) are cheaper. Note that on agentic workloads dominated by cache reads, Fable 5.1's effective cost drops up to ~45%.
Sources: each provider's official pricing page (verified 2026-09-01). See full pricing comparison.
Ideal Use Cases
Fable 5.1 shines on long-running, high-difficulty reasoning and agentic work.
Long-horizon agents
Multi-step autonomous runs. Cache-read price cut improves cost efficiency.
Hard coding & debugging
Root-causing rare crashes other models miss.
Scientific research & knowledge work
More than 2× Fable 5 on Terminal-Bench-Science. Complex analysis and hypothesis generation.
Hard reasoning
60.9% on Humanity's Last Exam (no tools). Tough multidisciplinary problems.
Computer use
77.9% OSWorld 2.0 (partial). GUI-driven automation.
Business workflows
31.4% AutomationBench (~1.8× Fable 5's 17.1%). Autonomous routine work.
Claude Family Selection Guide
| Model | Input | Output | When to Use |
|---|---|---|---|
| Claude Fable 5.1 ⬅ | $10.00 | $50.00 | Hardest, long-horizon agents and scientific research (max capability) |
| Claude Opus 5 | $5.00 | $25.00 | Standard coding, agents and enterprise work |
| Claude Sonnet 5 | $2.00 | $10.00 | Speed × intelligence balance. High-volume, daily work |
| Claude Haiku 4.5 | $1.00 | $5.00 | Fastest, high-volume, classification. Cost-first |
💡 Strategy: Claude Opus 5 ($5/$25) is often sufficient. Escalate to Fable 5.1 when Opus 5 at higher effort still falls short. For cybersecurity / life-sciences work blocked by safeguards, Mythos 5.1 (application required).
Estimate Your Actual Costs
Compare token costs for Claude Fable 5.1 and all major models. Just enter your token counts.
🧮 Open Token Calculator →📊 Full Pricing Comparison · 🛡️ Claude Mythos 5.1 · 🗓️ Release Timeline · 🔗 Anthropic Announcement
⚠️ Disclaimer
- Pricing and specs verified against Anthropic's official pages (platform.claude.com / anthropic.com) on 2026-09-01. Subject to change without notice. Always check official pages before contracting.
- This site is informational only. We are not affiliated with or endorsed by any provider.
- Benchmark scores are as published by Anthropic. Your mileage may vary.