Claude Fable 5.2 vs Gemini 3.1 Pro: pricing and benchmarks
Gemini 3.1 Pro is 75% cheaper on input tokens ($2.00 vs $8.00 per 1M). Gemini 3.1 Pro is 70% cheaper on output tokens ($12.00 vs $40.00 per 1M). On our document Q&A workload (50,000 questions a month), Gemini 3.1 Pro costs $1,160 a month versus $4,400 for Claude Fable 5.2, 74% less. Epoch AI has not published a capability index score for Claude Fable 5.2 yet.
Which should you choose?
Epoch AI has not published a capability index score for Claude Fable 5.2 yet.
Gemini 3.1 Pro costs $4.50 per 1M tokens (3:1 input-to-output mix) vs $16.00 for Claude Fable 5.2, 72% less.
Pricing and specs
| Claude Fable 5.2 | Gemini 3.1 Pro | |
|---|---|---|
| Provider | Anthropic | |
| API model ID | claude-fable-5-2 | gemini-3.1-pro-preview |
| Input / 1M tokens | $8.00 | $2.00 |
| Cached input / 1M tokens | $0.20 | $0.20 |
| Output / 1M tokens | $40.00 | $12.00 |
| Long-context rates | — | $4.00 in / $18.00 out above 200K prompt tokens |
| Context window | 1M tokens | 1.05M tokens |
| Max output | 128K tokens | 66K tokens |
| Batch discount | 50% off | — |
Benchmarks
| Claude Fable 5.2 | Gemini 3.1 Pro | |
|---|---|---|
| Epoch Capabilities Index | — | 154.7 |
| GPQA Diamond· Science reasoning | — | 94.4% |
| FrontierMath (Tiers 1–3)· Advanced math | — | 59.6% |
| SimpleQA Verified· Factual accuracy | — | 73.5% |
| ARC-AGI-2· Abstract reasoning | — | 77.1% |
| DeepSWE· Coding | — | 11.7% |
| APEX-Agents· Agentic work | — | 35.3% |
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 5.2 | Gemini 3.1 Pro | Difference |
|---|---|---|---|
Support chatbot 100,000 replies a month, ~1,500 input tokens (system prompt + history) and ~400 output tokens each. | $2,800 | $780.00 | Gemini 3.1 Pro 72% cheaper |
Document Q&A (RAG) 50,000 questions a month with ~8,000 tokens of retrieved context and ~600 output tokens each. | $4,400 | $1,160 | Gemini 3.1 Pro 74% 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. | $1,816 | $536.00 | Gemini 3.1 Pro 70% cheaper |
Cached chatbot The same 100,000-reply support chatbot, but 60% of each prompt (system prompt + conversation history) is served from the prompt cache. | $2,098 | $618.00 | Gemini 3.1 Pro 71% cheaper |
Meeting notes 10,000 meetings a month summarized from ~12,000-token transcripts, ~1,000 output tokens each. | $1,360 | $360.00 | Gemini 3.1 Pro 74% cheaper |
Bulk translation 200,000 short translations a month, ~800 input and ~800 output tokens each. | $7,680 | $2,240 | Gemini 3.1 Pro 71% cheaper |
Content moderation 1,000,000 classifications a month, ~400 input tokens and ~80 output tokens each. | $6,400 | $1,760 | Gemini 3.1 Pro 73% cheaper |
Article drafting 300 long-form articles a month written from a ~4,000-token brief and outline, ~5,000 output tokens each. | $69.60 | $20.40 | Gemini 3.1 Pro 71% cheaper |
Code review bot 30,000 pull-request reviews a month, ~5,000 input tokens each (30% cached repository context) and ~700 output tokens. | $1,689 | $471.00 | Gemini 3.1 Pro 72% cheaper |
Invoice extraction 100,000 documents a month parsed into structured JSON, ~1,200 input and ~250 output tokens each. | $1,960 | $540.00 | Gemini 3.1 Pro 72% 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 5.2 vs Gemini 3.1 Pro cost calculator
- $1,160/mo$0.02 / req
- Claude Fable 5.2Anthropic$4,400/mo$0.09 / req
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 5.2 pricing notes
Anthropic’s newest Fable model for demanding reasoning and long-horizon agentic work, priced below Fable 5.1.
- Cache hits cost 2.5% of the base input price ($0.20 per 1M tokens).
- Cache writes cost $10 (5-minute cache) or $16 (1-hour cache) per 1M tokens.
- Fast mode costs $16 input / $80 output per 1M tokens.
- US-only inference (inference_geo: "us") costs 1.1x.
Gemini 3.1 Pro pricing notes
Google’s Gemini 3.1 Pro model, currently offered as a preview.
- Prompts over 200K tokens are billed at $4 input / $18 output per 1M tokens.
- No free tier on the Gemini API.
- Output price includes thinking tokens.
Frequently asked questions
- Is Claude Fable 5.2 cheaper than Gemini 3.1 Pro?
- Gemini 3.1 Pro is 75% cheaper on input tokens ($2.00 vs $8.00 per 1M). Gemini 3.1 Pro is 70% cheaper on output tokens ($12.00 vs $40.00 per 1M). On our document Q&A workload (50,000 questions a month), Gemini 3.1 Pro costs $1,160 a month versus $4,400 for Claude Fable 5.2, 74% less.
- Which is more capable, Claude Fable 5.2 or Gemini 3.1 Pro?
- Epoch AI has not published a capability index score for Claude Fable 5.2 yet.
- How much does Claude Fable 5.2 cost per 1M tokens?
- Claude Fable 5.2 costs $8.00 per 1M input tokens and $40.00 per 1M output tokens, and $0.20 per 1M cached input tokens on Anthropic’s standard tier.
- How much does Gemini 3.1 Pro cost per 1M tokens?
- Gemini 3.1 Pro costs $2.00 per 1M input tokens and $12.00 per 1M output tokens, and $0.20 per 1M cached input tokens on Google’s standard tier.
- Which has the larger context window, Claude Fable 5.2 or Gemini 3.1 Pro?
- Gemini 3.1 Pro has the larger context window: 1.05M tokens versus 1M for Claude Fable 5.2.