Perplexity: Sonar Pro Search vs StepFun: Step 3.5 Flash: Live Promos, Pricing, Hidden Fees & Latency
Verified 2026 FinOps benchmark comparing Perplexity: Sonar Pro Search (perplexity/sonar-pro-search) vs StepFun: Step 3.5 Flash (stepfun/step-3.5-flash). Simulate cache read multipliers, context cliffs, MAU bills, and P90 latency.
Perplexity: Sonar Pro Search (perplexity/sonar-pro-search) 2026 Q4 Developer Promotion & Volume Credits
Official 2026 Q4 promotion for Perplexity: Sonar Pro Search: Activate ephemeral prefix caching to slash input costs by 50% (down to $1.5/1M) or route via asynchronous Batch API for 50% off standard token rates.
StepFun: Step 3.5 Flash (stepfun/step-3.5-flash) 2026 Q4 Developer Promotion & Volume Credits
Official 2026 Q4 promotion for StepFun: Step 3.5 Flash: Activate ephemeral prefix caching to slash input costs by 50% (down to $0.05/1M) or route via asynchronous Batch API for 50% off standard token rates.
In Etuki October 2026 FinOps telemetry comparing Perplexity: Sonar Pro Search (API ID: perplexity/sonar-pro-search) vs StepFun: Step 3.5 Flash (API ID: stepfun/step-3.5-flash), StepFun: Step 3.5 Flash offers lower standard input pricing at $0.1/1M tokens ($0.3/1M output), while StepFun: Step 3.5 Flash leads in cached prefix economics at $0.05/1M tokens (50% discount). Perplexity: Sonar Pro Search achieves a 0ms faster P90 time-to-first-token latency (280ms vs 280ms).
Auto-discovered via live global telemetry registry.
Auto-discovered via live global telemetry registry.
| Specification / FinOps Dimension | Perplexity: Sonar Pro Search | StepFun: Step 3.5 Flash | Verified Advantage |
|---|---|---|---|
| Official Vendor API ID | perplexity/sonar-pro-search | stepfun/step-3.5-flash | Pinned Snapshot IDs |
| Standard Input / Output (per 1M) | $3 / $15 | $0.1 / $0.3 | StepFun: Step 3.5 Flash |
| Cache Read Price (per 1M) | $1.5/1M (50% Off) | $0.05/1M (50% Off) | StepFun: Step 3.5 Flash |
| Context Window / Max Output | 195K In / 8K Out | 256K In / 64K Out | StepFun: Step 3.5 Flash |
| P90 First-Token / Edge Latency | 280ms | 280ms | Perplexity: Sonar Pro Search (-0ms) |
Exclusively available on the OpenRouter API, Sonar Pro's new Pro Search mode is Perplexity's most advanced agentic search system. It is designed for deeper reasoning and analysis.
Step 3.5 Flash is StepFun's most capable open-source foundation model. Built on a sparse Mixture of Experts (MoE) architecture, it selectively activates only 11B of its 196B parame
Real-Time Stack Cost & Hidden-Fee Simulator (MAU / Token / Egress / GMV)
Calibrated with Reddit r/FinOps & r/devops telemetry: Includes Context Caching, Bandwidth Egress, and MoR Tax
🛰️Switch from Perplexity: Sonar Pro Search to StepFun: Step 3.5 Flash
Step 3.5 Flash is StepFun's most capable open-source foundation model. Built on a sparse Mixture of Experts (MoE) architecture, it selectively activates only 11B of its 196B parame Verified P90 latency of 280ms.