Claude Opus 5.5 vs Gemini 3.6 Flash: pricing and benchmarks
Gemini 3.6 Flash is 81% cheaper on input tokens ($0.75 vs $4.00 per 1M). Gemini 3.6 Flash is 81% cheaper on output tokens ($3.75 vs $20.00 per 1M). On our document Q&A workload (50,000 questions a month), Gemini 3.6 Flash costs $412.50 a month versus $2,200 for Claude Opus 5.5, 81% less. Claude Opus 5.5 scores 166.8 on the Epoch Capabilities Index vs 154.2 for Gemini 3.6 Flash.
Prices verified October 17, 2026.
Which should you choose?
Claude Opus 5.5 scores 166.8 on the Epoch Capabilities Index vs 154.2 for Gemini 3.6 Flash.
Claude Opus 5.5 scores 91.2% on FrontierMath (Tiers 1–3) vs 58.9% for Gemini 3.6 Flash.
Gemini 3.6 Flash costs $1.50 per 1M tokens (3:1 input-to-output mix) vs $8.00 for Claude Opus 5.5, 81% less.
A trade-off: Claude Opus 5.5 is 12.6 ECI points more capable but costs 5.3x as much as Gemini 3.6 Flash.
Pricing and specs
| Claude Opus 5.5 | Gemini 3.6 Flash | |
|---|---|---|
| Provider | Anthropic | |
| API model ID | claude-opus-5-5 | gemini-3.6-flash |
| Input / 1M tokens | $4.00 | $0.75 |
| Cached input / 1M tokens | $0.20 | $0.075 |
| Output / 1M tokens | $20.00 | $3.75 |
| Long-context rates | — | — |
| Context window | 1M tokens | 1.05M tokens |
| Max output | 128K tokens | 66K tokens |
| Batch discount | 50% off | 50% off |
Benchmarks
| Claude Opus 5.5 | Gemini 3.6 Flash | |
|---|---|---|
| Epoch Capabilities Index | 166.8 | 154.2 |
| GPQA Diamond· Science reasoning | 90.6% | 94.1% |
| FrontierMath (Tiers 1–3)· Advanced math | 91.2% | 58.9% |
| SimpleQA Verified· Factual accuracy | 72.2% | 66.2% |
| ARC-AGI-2· Abstract reasoning | 93.3% | 60.4% |
| DeepSWE· Coding | — | 46.7% |
| APEX-Agents· Agentic work | 73.5% | 46.9% |
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 Opus 5.5 | Gemini 3.6 Flash | Difference |
|---|---|---|---|
Support chatbot 100,000 replies a month, ~1,500 input tokens (system prompt + history) and ~400 output tokens each. | $1,400 | $262.50 | Gemini 3.6 Flash 81% cheaper |
Document Q&A (RAG) 50,000 questions a month with ~8,000 tokens of retrieved context and ~600 output tokens each. | $2,200 | $412.50 | Gemini 3.6 Flash 81% 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. | $936.00 | $186.00 | Gemini 3.6 Flash 80% 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 Opus 5.5 vs Gemini 3.6 Flash cost calculator
- $412.50/mo$0.0083 / request
- Claude Opus 5.5Anthropic$2,200/mo$0.04 / 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 Opus 5.5 pricing notes
Anthropic’s recommended default model for most workloads, with adaptive thinking always on.
- Cache reads cost 5% of the input price, against 10% on Claude Opus 5 and Sonnet 5.
- Cache writes cost $5 (5-minute cache) or $8 (1-hour cache) per 1M tokens.
- Fast mode costs $8 input / $40 output per 1M tokens.
- US-only inference (inference_geo: "us") costs 1.1x.
Gemini 3.6 Flash pricing notes
Google’s previous-generation Flash model, which replaced Gemini 3.5 Flash in October 2026.
- Introductory price through December 31, 2026. From January 1, 2027: $1.50 input, $0.15 cached, $7.50 output per 1M tokens.
- Requests to the retired gemini-3.5-flash model ID are routed to Gemini 3.6 Flash.
- Output price includes thinking tokens.
- Priority inference costs 1.8x the standard rate.
Frequently asked questions
- Is Claude Opus 5.5 cheaper than Gemini 3.6 Flash?
- Gemini 3.6 Flash is 81% cheaper on input tokens ($0.75 vs $4.00 per 1M). Gemini 3.6 Flash is 81% cheaper on output tokens ($3.75 vs $20.00 per 1M). On our document Q&A workload (50,000 questions a month), Gemini 3.6 Flash costs $412.50 a month versus $2,200 for Claude Opus 5.5, 81% less.
- Which is more capable, Claude Opus 5.5 or Gemini 3.6 Flash?
- Claude Opus 5.5 scores 166.8 on the Epoch Capabilities Index vs 154.2 for Gemini 3.6 Flash.
- How much does Claude Opus 5.5 cost per 1M tokens?
- Claude Opus 5.5 costs $4.00 per 1M input tokens and $20.00 per 1M output tokens, and $0.20 per 1M cached input tokens on Anthropic’s standard tier.
- How much does Gemini 3.6 Flash cost per 1M tokens?
- Gemini 3.6 Flash costs $0.75 per 1M input tokens and $3.75 per 1M output tokens, and $0.075 per 1M cached input tokens on Google’s standard tier.
- Which has the larger context window, Claude Opus 5.5 or Gemini 3.6 Flash?
- Gemini 3.6 Flash has the larger context window: 1.05M tokens versus 1M for Claude Opus 5.5.