Gemini 3.5 Flash vs Claude Opus 4.8
Head-to-head specifications
| Metric | Gemini 3.5 Flash | Claude Opus 4.8 | Difference |
|---|---|---|---|
| Intelligence Index | 50.0 | 56.0 | -10.7% |
| Coding Index | 70.1 | 74.3 | -5.7% |
| Agentic Index | 37.4 | 47.2 | — |
| Context window | 1M tokens | 1M tokens | — |
| Blended price ($/1M tokens) | $0.76 | $1.38 | -44.9% |
| Output speed (tokens/s) | 161 | 53 | +203.8% |
| Access | Proprietary API | Proprietary API | — |
- Claude Opus 4.8 leads overall capability (Intelligence Index 56.0 vs 50.0).
- Gemini 3.5 Flash is the cheaper model to run at $0.76/1M blended tokens — about 1.8× cheaper.
Verdict: Gemini 3.5 Flash or Claude Opus 4.8?
Gemini 3.5 Flash advantages
- Affordability (+45%)
- Output speed (+67%)
Claude Opus 4.8 advantages
- General intelligence (+11%)
- Coding ability (+6%)
- Agentic task performance (+21%)
Which should you choose?
- Choose the Gemini 3.5 Flash if you want the lowest cost per token at scale.
- Choose the Claude Opus 4.8 if you need the strongest overall reasoning and accuracy.
- Choose the Gemini 3.5 Flash if low latency and fast generation matter for your application.
Value for money
Gemini 3.5 Flash offers more intelligence per dollar (1.6× the Intelligence-Index-per-cost of the alternative), making it the stronger value for high-volume use.
Gemini 3.5 Flash vs Claude Opus 4.8: which should you choose?
Gemini 3.5 Flash — Google multimodal model with an Intelligence Index of 50, a 1M-token context window and a blended price of $0.76/1M tokens.
Claude Opus 4.8 — Anthropic multimodal model with an Intelligence Index of 56, a 1M-token context window and a blended price of $1.38/1M tokens.
Gemini 3.5 Flash vs Claude Opus 4.8: Claude Opus 4.8 scores higher on the Intelligence Index. Claude Opus 4.8 leads overall capability (Intelligence Index 56.0 vs 50.0). Gemini 3.5 Flash is the cheaper model to run at $0.76/1M blended tokens — about 1.8× cheaper.
Capability: intelligence, coding and agentic work
On the composite Intelligence Index the Claude Opus 4.8 scores 56.0 versus 50.0. For software development, the Coding Index puts Claude Opus 4.8 ahead (74.3 vs 70.1). On agentic, multi-step tool-use tasks, Claude Opus 4.8 measures stronger. Composite indices summarize many evaluations, but always test on your own workload before committing.
Context window and speed
The Gemini 3.5 Flash accepts up to 1 million tokens per request, which sets how much documentation, transcript or code it can reason over at once. In measured throughput, Gemini 3.5 Flash generates faster (161 vs 53 tokens/s), which matters for interactive apps and high-volume pipelines.
Pricing and access
At blended per-token rates, Gemini 3.5 Flash is the cheaper model to run ($0.76 vs $1.38 per 1M tokens). Gemini 3.5 Flash is proprietary api and Claude Opus 4.8 is proprietary api. Open-weight models can be self-hosted, trading per-call cost for infrastructure you manage; for production also weigh rate limits, throughput and data-residency requirements.
The verdict
Both are credible choices in the ai model comparison space; the specification table above lays out every metric so you can weigh the trade-offs that matter to you. Pick the one whose strengths line up with how you will actually use it.
Frequently asked questions
Is the Gemini 3.5 Flash better than the Claude Opus 4.8?
Claude Opus 4.8 takes the overall edge, though Gemini 3.5 Flash wins in specific areas worth weighing. Claude Opus 4.8 leads overall capability (Intelligence Index 56.0 vs 50.0).
What is the main difference between the Gemini 3.5 Flash and the Claude Opus 4.8?
Claude Opus 4.8 leads overall capability (Intelligence Index 56.0 vs 50.0). Gemini 3.5 Flash is the cheaper model to run at $0.76/1M blended tokens — about 1.8× cheaper.
Which is better value?
Gemini 3.5 Flash offers more intelligence per dollar (1.6× the Intelligence-Index-per-cost of the alternative), making it the stronger value for high-volume use.
Which should I choose?
Choose the Gemini 3.5 Flash if you want the lowest cost per token at scale. Choose the Claude Opus 4.8 if you need the strongest overall reasoning and accuracy.
Methodology
Large language models are compared on independent leaderboard metrics: an Intelligence Index (a composite of reasoning and knowledge evaluations), Coding and Agentic indices where measured, community arena Elo, maximum context window, a blended API price per million tokens (weighted across cache-hit, input and output rates), and measured output speed in tokens per second. Where a model ships multiple reasoning-effort variants, we report its strongest variant. Benchmarks capture only part of real-world quality, which also depends on tool use, latency, safety and task fit — and this space moves quickly, so figures reflect the leaderboard snapshot on the page date.