Side-by-side comparison of pricing, 12 benchmarks, and generation speed.
| Metric | Sonar Reasoning | Gemini 3.5 Flash (high) |
|---|---|---|
| Input ($/M tokens) | — | $1.5 |
| Output ($/M tokens) | — | $9 |
Verdict. Gemini 3.5 Flash (high) takes the aggregate benchmark matchup 2–0 across 2 categories. Real workloads usually care about a handful of specific tasks — see the per-benchmark table above.
Pricing. Pricing varies significantly between these models — check the table above for the exact per-token rates. Many production workloads actually surface input-token cost (retrieval-augmented prompts, code-context windows), so factor both directions.
Strengths. Sonar Reasoning is strongest on Intelligence Index (8.7). Gemini 3.5 Flash (high) leads on Coding Index (70.1), Intelligence Index (33.0).
Speed. Speed data is incomplete for this pair; benchmark and price should decide.
Provider. Perplexity and Google sell to overlapping but distinct developer audiences: Perplexity tends to ship frontier reasoning models with premium positioning, while Google often prices more aggressively. Your existing vendor relationships, billing, and SLA preferences may matter as much as the raw numbers above.
Recommendation. Both models have legitimate use cases — the right answer depends on whether you are optimizing for benchmark ceiling, latency, or unit cost. Start with the cheaper / faster model, evaluate against your specific task, and only switch if the upgrade shows a meaningful lift.
Data from Artificial Analysis API — 12 benchmarks
Gemini 3.5 Flash (high) is cheaper overall. Its blended price (3:1 input/output ratio) is $3.38/M tokens vs $—/M for Sonar Reasoning.
Gemini 3.5 Flash (high) wins 2 out of 12 benchmarks compared to 0 for Sonar Reasoning. See the detailed benchmark chart above for per-category results.
Gemini 3.5 Flash (high) generates tokens faster at 216 tok/s vs — tok/s. However, Gemini 3.5 Flash (high) has lower time-to-first-token (18.36s vs —s).
Choose based on your priorities: Gemini 3.5 Flash (high) for lower cost, Gemini 3.5 Flash (high) for stronger benchmark performance, and Gemini 3.5 Flash (high) for faster generation. For latency-sensitive apps, check the TTFT comparison above.