Gemini 3.5 Flash vs Claude Opus 4.6
Gemini 3.5 Flash comes out ahead, 69 to 61 on our weighted score, and it is the cheaper option too.
- Our pick
Google
Gemini 3.5 Flash
69/100- ECI154.5
- Price$1.50 / $9.00
- Context1.05M
Anthropic
Claude Opus 4.6
61/100- ECI155.3
- Price$5.00 / $25.00
- Context1M
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Gemini 3.5 Flash is our pick
Gemini 3.5 Flash is the better all-round choice, scoring 69/100 against Claude Opus 4.6 (61). It leads on price and inputs & features. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.
- CapabilityClaude Opus 4.6Capabilities Index (ECI): Claude Opus 4.6 155.3 · Gemini 3.5 Flash 154.5
- Lowest priceGemini 3.5 FlashGemini 3.5 Flash $3.38 · Claude Opus 4.6 $10.00 per 1M tokens (3:1 blend)
- Longest contextGemini 3.5 FlashGemini 3.5 Flash 1,048,576 · Claude Opus 4.6 1,000,000 tokens
- Widest inputsGemini 3.5 FlashGemini 3.5 Flash: Text, Images, PDFs, Audio, Video · Claude Opus 4.6: Text, Images, PDFs
- Self-hostingNo open weightsBoth are available only through APIs
| Measure | Weight | Gemini 3.5 Flash | Claude Opus 4.6 |
|---|---|---|---|
| CapabilityCapabilities Index (ECI) | 50% | 84 | 85 |
| Price | 25% | 25 | 2 |
| Inputs & features | 15% | 100 | 80 |
| Context window | 10% | 61 | 60 |
| Overall | 100% | 69/100 | 61/100 |
Every spec in one table
Highlighted cells lead their row. Dashes mean the data is not published.
| Specification | ||
|---|---|---|
| Capability | ||
| Capabilities Index (ECI) | 154.5 | 155.3 (best) |
| ECI rank | #33 of 148 | #27 of 148 (best) |
| GPQA DiamondGraduate-level science questions | 92.8% (best) | 90.5% |
| FrontierMath Tiers 1–3Research-level mathematics | 62.8% | 66.0% (best) |
| OTIS Mock AIME 2024–2025Competition mathematics | 95.6% (best) | 94.4% |
| SWE-bench VerifiedFixing real GitHub issues | 79.3% (best) | 78.7% |
| SimpleQA VerifiedShort factual questions | 66.2% (best) | 47.0% |
| Price per million tokens | ||
| Input | $1.50 (best) | $5.00 |
| Output | $9.00 (best) | $25.00 |
| Cached input | $0.15 (best) | $0.50 |
| Blended (3:1) | $3.38 (best) | $10.00 |
| Long-context rate | Same rate | Same rate |
| Price source | Official Google API | Official Anthropic API |
| Limits | ||
| Context window | 1,048,576 tokens (best) | 1,000,000 tokens |
| Max output | 65,536 tokens | 128,000 tokens (best) |
| Inputs and features | ||
| Text | Yes | Yes |
| Images | Yes | Yes |
| PDFs | Yes | Yes |
| Audio | Yes | No |
| Video | Yes | No |
| Reasoning | Yesminimal · low · medium · high | Yeslow · medium · high · max |
| Tool calling | Yes | Yes |
| Structured output | Yes | Yes |
| Availability | ||
| Weights | Proprietary | Proprietary |
| API model ID | gemini-3.5-flash | claude-opus-4-6 |
| API providers | 32 | 33 (best) |
| Released | May 19, 2026 | Feb 5, 2026 |
| Knowledge cutoff | Jan 2025 | May 31, 2025 |
What would a month cost?
Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.
Gemini 3.5 Flash$33.00
Claude Opus 4.6$100.00
Which should you choose?
Which is better: Gemini 3.5 Flash or Claude Opus 4.6?
Gemini 3.5 Flash is the better all-round choice, scoring 69/100 against Claude Opus 4.6 (61). It leads on price and inputs & features. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.
Which is cheaper, Gemini 3.5 Flash or Claude Opus 4.6?
Gemini 3.5 Flash is cheaper at $1.50 input / $9.00 output per million tokens (official Google API price). Claude Opus 4.6 costs $5.00 input / $25.00 output per million tokens (official Anthropic API price). At a typical mix of three input tokens to one output token, that is $3.38 per million tokens for Gemini 3.5 Flash versus $10.00 for Claude Opus 4.6 (3× as much).
Which scores higher on benchmarks?
Claude Opus 4.6 scores higher on the Capabilities Index (ECI): Claude Opus 4.6 155.3 (#27 of 148) and Gemini 3.5 Flash 154.5 (#33 of 148). The confidence ranges of the top two overlap (153.4–157.3 vs 152.5–156.6), so treat the gap as small. On individual benchmarks: GPQA Diamond — Gemini 3.5 Flash 92.8%, Claude Opus 4.6 90.5%; FrontierMath Tiers 1–3 — Claude Opus 4.6 66.0%, Gemini 3.5 Flash 62.8%; OTIS Mock AIME 2024–2025 — Gemini 3.5 Flash 95.6%, Claude Opus 4.6 94.4%; SWE-bench Verified — Gemini 3.5 Flash 79.3%, Claude Opus 4.6 78.7%; SimpleQA Verified — Gemini 3.5 Flash 66.2%, Claude Opus 4.6 47.0%.
Which is better for coding?
Gemini 3.5 Flash resolves more real GitHub issues on SWE-bench Verified: Gemini 3.5 Flash 79.3% and Claude Opus 4.6 78.7%. Both support tool calling for agent workflows.
Which has the bigger context window?
Gemini 3.5 Flash has the largest context window at 1,048,576 tokens, against 1,000,000 for Claude Opus 4.6. Maximum output per response: Gemini 3.5 Flash up to 65,536, Claude Opus 4.6 up to 128,000 tokens.
Which can read images, PDFs, audio or video?
Gemini 3.5 Flash accepts text, images, PDFs, audio and video; Claude Opus 4.6 accepts text, images and PDFs. Gemini 3.5 Flash handles the widest range of inputs.
Are any of these open source?
No. Gemini 3.5 Flash and Claude Opus 4.6 are proprietary and only available through APIs and apps.
Which is newer?
Gemini 3.5 Flash is the newest, released May 19, 2026. Claude Opus 4.6 came out Feb 5, 2026. Knowledge cutoff: Gemini 3.5 Flash Jan 2025, Claude Opus 4.6 May 31, 2025.
How do you decide the winner?
Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Oct 4, 2026.