GPT-5.4 Pro vs Step 3.7 Flash
GPT-5.4 Pro (2026) and Step 3.7 Flash (2026) are frontier-tier reasoning models from OpenAI and StepFun. GPT-5.4 Pro ships a 1.05m-token context window, while Step 3.7 Flash ships a 256k-token context window. On pricing, GPT-5.4 Pro ranges from $30 to $60/1M input tokens by tier; Step 3.7 Flash costs $0.20/1M input tokens. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.
GPT-5.4 Pro fits 4x more tokens; pick it for long-context work and Step 3.7 Flash for tighter calls.
Decision scorecard
Local evidence first| Signal | GPT-5.4 Pro | Step 3.7 Flash |
|---|---|---|
| Best for | reasoning-heavy apps, multimodal apps, and tool-calling agents | reasoning-heavy apps, multimodal apps, and tool-calling agents |
| Decision fit | Coding, RAG, and Agents | Coding, RAG, and Agents |
| Context window | 1.05m | 256k |
| Cheapest output | $180/1M tokens | $1.15/1M tokens |
| Provider routes | 3 tracked | 3 tracked |
| Shared benchmarks | 0 rows | 0 rows |
Decision tradeoffs
- GPT-5.4 Pro has the larger context window for long prompts, retrieval packs, or transcript analysis.
- GPT-5.4 Pro uniquely exposes Code execution in local model data.
- Local decision data tags GPT-5.4 Pro for Coding, RAG, and Agents.
- Step 3.7 Flash has the lower cheapest tracked output price at $1.15/1M tokens.
- Local decision data tags Step 3.7 Flash for Coding, RAG, and Agents.
Monthly cost at traffic
Estimate token spend from the cheapest tracked input and output route or tier on this page.
GPT-5.4 Pro
$69,000
Cheapest tracked route/tier: OpenRouter
Step 3.7 Flash
$448
Cheapest tracked route/tier: StepFun
Estimated monthly gap: $68,553. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.
Switch friction
- Provider overlap exists on OpenRouter; start route-level A/B tests there.
- Step 3.7 Flash is $179/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
- Check replacement coverage for Code execution before moving production traffic.
- Provider overlap exists on OpenRouter; start route-level A/B tests there.
- GPT-5.4 Pro is $179/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
- GPT-5.4 Pro adds Code execution in local capability data.
Specs
| Specification | ||
|---|---|---|
| Released | 2026-03-01 | 2026-05-29 |
| Context window | 1.05m | 256k |
| Parameters | — | 198B (11B active) |
| Architecture | decoder only | mixture of experts |
| License | Proprietary | Proprietary |
| Openness | Proprietary | Proprietary |
| Commercial use | Commercial use with conditions | Commercial use with conditions |
| Knowledge cutoff | 2025-08 | - |
Pricing and availability
| Pricing attribute | GPT-5.4 Pro | Step 3.7 Flash |
|---|---|---|
| Input price |
| $0.20/1M tokens |
| Output price |
| $1.15/1M tokens |
| Providers |
Capabilities
| Capability | GPT-5.4 Pro | Step 3.7 Flash |
|---|---|---|
| Vision | Yes | Yes |
| Multimodal | Yes | Yes |
| Reasoning | Yes | Yes |
| Function calling | Yes | Yes |
| Tool use | Yes | Yes |
| Structured outputs | Yes | Yes |
| Code execution | Yes | No |
| IDE integration | No | No |
| Computer use | No | No |
| Parallel agents | No | No |
Benchmarks
No shared benchmark rows are currently sourced for this pair.
Deep dive
The capability footprint differs most on code execution: GPT-5.4 Pro. Both models share vision, multimodal input, reasoning mode, and function calling, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.
For cost, GPT-5.4 Pro lists tiered pricing: 0-272,000t is $30/1M input and $180/1M output; 272,000t+ is $60/1M input and $270/1M output, while Step 3.7 Flash lists $0.20/1M input and $1.15/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts Step 3.7 Flash lower by about $74.52 per million blended tokens. For tiered rows, this cheapest-track view can understate interactive or fast-lane spend, so compare the tier you will actually use. Availability is 3 providers versus 3, so concentration risk also matters.
Choose GPT-5.4 Pro when coding workflow support and larger context windows are central to the workload. Choose Step 3.7 Flash when vision-heavy evaluation and lower input-token cost are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship.
FAQ
Which has a larger context window, GPT-5.4 Pro or Step 3.7 Flash?
GPT-5.4 Pro supports 1.05m tokens, while Step 3.7 Flash supports 256k tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.
Which is cheaper, GPT-5.4 Pro or Step 3.7 Flash?
GPT-5.4 Pro lists tiered pricing: 0-272,000t is $30/1M input and $180/1M output; 272,000t+ is $60/1M input and $270/1M output. Step 3.7 Flash lists $0.20/1M input and $1.15/1M output tokens on the cheapest tracked provider. Compare the tier you will actually use; cheap async pricing can overstate savings for interactive workflows. Provider discounts or batch pricing can still change the final bill.
Is GPT-5.4 Pro or Step 3.7 Flash open source?
GPT-5.4 Pro is listed under Proprietary. Step 3.7 Flash is listed under Proprietary. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.
Which is better for vision, GPT-5.4 Pro or Step 3.7 Flash?
Both GPT-5.4 Pro and Step 3.7 Flash expose vision. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.
Which is better for multimodal input, GPT-5.4 Pro or Step 3.7 Flash?
Both GPT-5.4 Pro and Step 3.7 Flash expose multimodal input. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface.
Where can I run GPT-5.4 Pro and Step 3.7 Flash?
GPT-5.4 Pro is available on OpenRouter, OpenAI API, and Vercel AI Gateway. Step 3.7 Flash is available on StepFun, OpenRouter, and NVIDIA NIM. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
Continue comparing
Last reviewed: 2026-05-29. Data sourced from public model cards and provider documentation.