Claude Fable 5.1 vs Claude Haiku 5.5: pricing and benchmarks
Claude Haiku 5.5 is 99% cheaper on input tokens ($0.10 vs $10.00 per 1M). Claude Haiku 5.5 is 99% cheaper on output tokens ($0.50 vs $50.00 per 1M). On our document Q&A workload (50,000 questions a month), Claude Haiku 5.5 costs $55.00 a month versus $5,500 for Claude Fable 5.1, 99% less. Roughly tied. Claude Fable 5.1 scores 164.7 and Claude Haiku 5.5 scores 159.0 on the Epoch Capabilities Index, and their confidence intervals overlap.
Prices verified October 17, 2026.
Which should you choose?
Roughly tied. Claude Fable 5.1 scores 164.7 and Claude Haiku 5.5 scores 159.0 on the Epoch Capabilities Index, and their confidence intervals overlap.
Claude Fable 5.1 scores 90.2% on FrontierMath (Tiers 1–3) vs 75.1% for Claude Haiku 5.5.
Claude Haiku 5.5 costs $0.20 per 1M tokens (3:1 input-to-output mix) vs $20.00 for Claude Fable 5.1, 99% less.
Claude Haiku 5.5 delivers statistically similar overall capability for 99% less.
Pricing and specs
| Claude Fable 5.1 | Claude Haiku 5.5 | |
|---|---|---|
| Provider | Anthropic | Anthropic |
| API model ID | claude-fable-5-1 | claude-haiku-5-5 |
| Input / 1M tokens | $10.00 | $0.10 |
| Cached input / 1M tokens | $0.25 | $0.01 |
| Output / 1M tokens | $50.00 | $0.50 |
| Long-context rates | — | $0.50 in / $2.50 out above 100K prompt tokens |
| Context window | 1M tokens | 1M tokens |
| Max output | 128K tokens | 128K tokens |
| Batch discount | 50% off | 50% off |
Benchmarks
| Claude Fable 5.1 | Claude Haiku 5.5 | |
|---|---|---|
| Epoch Capabilities Index | 164.7 | 159.0 |
| GPQA Diamond· Science reasoning | — | 89.6% |
| FrontierMath (Tiers 1–3)· Advanced math | 90.2% | 75.1% |
| SimpleQA Verified· Factual accuracy | 70.8% | 23.8% |
| ARC-AGI-2· Abstract reasoning | 90.0% | — |
| DeepSWE· Coding | — | — |
| APEX-Agents· Agentic work | 68.6% | 56.1% |
Source: Epoch AI, best recorded result per model (CC BY 4.0). A dash means no published score. See all benchmarks
Monthly cost for real workloads
| Workload | Claude Fable 5.1 | Claude Haiku 5.5 | Difference |
|---|---|---|---|
Support chatbot 100,000 replies a month, ~1,500 input tokens (system prompt + history) and ~400 output tokens each. | $3,500 | $35.00 | Claude Haiku 5.5 99% cheaper |
Document Q&A (RAG) 50,000 questions a month with ~8,000 tokens of retrieved context and ~600 output tokens each. | $5,500 | $55.00 | Claude Haiku 5.5 99% cheaper |
Coding agent 10,000 agent steps a month, ~40,000 input tokens each (70% read from the prompt cache) and ~2,000 output tokens. | $2,270 | $24.80 | Claude Haiku 5.5 99% cheaper |
Estimates use standard list prices and ignore cache-write surcharges. Different tokenizers can count the same text differently, so test with your own prompts.
Claude Fable 5.1 vs Claude Haiku 5.5 cost calculator
- $55.00/mo$0.0011 / request
- Claude Fable 5.1Anthropic$5,500/mo$0.11 / request
Standard-tier list prices. Long-context rates apply automatically where the provider publishes a threshold. Excludes cache-write surcharges, taxes, batch and volume discounts.
Claude Fable 5.1 pricing notes
Anthropic’s model for demanding reasoning and long-horizon agentic work.
- Cache hits cost 2.5% of the base input price, versus 10% on other Claude models.
- Cache writes cost $12.50 (5-minute cache) or $20 (1-hour cache) per 1M tokens.
- Uses Anthropic’s newer tokenizer, which produces roughly 30% more tokens for the same text.
- US-only inference (inference_geo: "us") costs 1.1x.
Claude Haiku 5.5 pricing notes
Anthropic’s fastest, lowest-cost model, priced by prompt length, with a 1M-token context window.
- Prompts over 100K tokens, counting cache reads and writes, are billed at $0.50 input / $2.50 output per 1M tokens.
- Cache writes cost $0.125 (5-minute cache) or $0.20 (1-hour cache) per 1M tokens, 5x that above 100K tokens.
- US-only inference (inference_geo: "us") costs 1.1x.
Frequently asked questions
- Is Claude Fable 5.1 cheaper than Claude Haiku 5.5?
- Claude Haiku 5.5 is 99% cheaper on input tokens ($0.10 vs $10.00 per 1M). Claude Haiku 5.5 is 99% cheaper on output tokens ($0.50 vs $50.00 per 1M). On our document Q&A workload (50,000 questions a month), Claude Haiku 5.5 costs $55.00 a month versus $5,500 for Claude Fable 5.1, 99% less.
- Which is more capable, Claude Fable 5.1 or Claude Haiku 5.5?
- Roughly tied. Claude Fable 5.1 scores 164.7 and Claude Haiku 5.5 scores 159.0 on the Epoch Capabilities Index, and their confidence intervals overlap.
- How much does Claude Fable 5.1 cost per 1M tokens?
- Claude Fable 5.1 costs $10.00 per 1M input tokens and $50.00 per 1M output tokens, and $0.25 per 1M cached input tokens on Anthropic’s standard tier.
- How much does Claude Haiku 5.5 cost per 1M tokens?
- Claude Haiku 5.5 costs $0.10 per 1M input tokens and $0.50 per 1M output tokens, and $0.01 per 1M cached input tokens on Anthropic’s standard tier.
- Which has the larger context window, Claude Fable 5.1 or Claude Haiku 5.5?
- Both offer a 1M-token context window.