LLM Reference

Claude 3.5 Haiku vs Step 3.5 Flash

Claude 3.5 Haiku (2024) and Step 3.5 Flash (2026) are frontier-tier reasoning models from Anthropic and StepFun. Claude 3.5 Haiku ships a 200k-token context window, while Step 3.5 Flash ships a 256k-token context window. On pricing, Step 3.5 Flash costs $0.10/1M input tokens versus $0.80/1M for the alternative. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit.

Step 3.5 Flash is ~700% cheaper at $0.10/1M; pay for Claude 3.5 Haiku only for coding workflow support.

Decision scorecard

Local evidence first
SignalClaude 3.5 HaikuStep 3.5 Flash
Best forreasoning-heavy apps, multimodal apps, and provider-routed productionreasoning-heavy apps
Decision fitCoding, RAG, and AgentsLong context
Context window200k256k
Cheapest output$4/1M tokens$0.30/1M tokens
Provider routes6 tracked1 tracked
Shared benchmarks0 rows0 rows

Decision tradeoffs

Choose Claude 3.5 Haiku when...
  • Claude 3.5 Haiku has broader tracked provider coverage for fallback and procurement flexibility.
  • Claude 3.5 Haiku uniquely exposes Vision, Structured outputs, and Code execution in local model data.
  • Local decision data tags Claude 3.5 Haiku for Coding, RAG, and Agents.
Choose Step 3.5 Flash when...
  • Step 3.5 Flash has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • Step 3.5 Flash has the lower cheapest tracked output price at $0.30/1M tokens.
  • Local decision data tags Step 3.5 Flash for Long context.

Monthly cost at traffic

Estimate token spend from the cheapest tracked input and output route or tier on this page.

Lower estimate Step 3.5 Flash

Claude 3.5 Haiku

$1,640

Cheapest tracked route/tier: Anthropic

Step 3.5 Flash

$155

Cheapest tracked route/tier: OpenRouter

Estimated monthly gap: $1,485. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

Claude 3.5 Haiku -> Step 3.5 Flash
  • Provider overlap exists on OpenRouter; start route-level A/B tests there.
  • Step 3.5 Flash is $3.70/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
  • Check replacement coverage for Vision, Structured outputs, and Code execution before moving production traffic.
Step 3.5 Flash -> Claude 3.5 Haiku
  • Provider overlap exists on OpenRouter; start route-level A/B tests there.
  • Claude 3.5 Haiku is $3.70/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • Claude 3.5 Haiku adds Vision, Structured outputs, and Code execution in local capability data.

Specs

Specification
Released2024-10-222026-01-29
Context window200k256k
Parameters196B (11B active)
Architecturedecoder onlymixture of experts
LicenseUnknownOpen Source
Knowledge cutoff--

Pricing and availability

Pricing attributeClaude 3.5 HaikuStep 3.5 Flash
Input price$0.80/1M tokens$0.10/1M tokens
Output price$4/1M tokens$0.30/1M tokens
Providers

Capabilities

CapabilityClaude 3.5 HaikuStep 3.5 Flash
VisionYesNo
MultimodalNoNo
ReasoningYesYes
Function callingNoNo
Tool useNoNo
Structured outputsYesNo
Code executionYesNo
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

No shared benchmark rows are currently sourced for this pair.

Deep dive

The capability footprint differs most on vision: Claude 3.5 Haiku, structured outputs: Claude 3.5 Haiku, and code execution: Claude 3.5 Haiku. Both models share reasoning mode, 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, Claude 3.5 Haiku lists $0.80/1M input and $4/1M output tokens on the cheapest tracked provider, while Step 3.5 Flash lists $0.10/1M input and $0.30/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts Step 3.5 Flash lower by about $1.60 per million blended tokens. Availability is 6 providers versus 1, so concentration risk also matters.

Choose Claude 3.5 Haiku when coding workflow support and broader provider choice are central to the workload. Choose Step 3.5 Flash when long-context analysis, larger context windows, 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. This keeps the decision grounded in measurable tradeoffs instead of brand-level assumptions.

FAQ

Which has a larger context window, Claude 3.5 Haiku or Step 3.5 Flash?

Step 3.5 Flash supports 256k tokens, while Claude 3.5 Haiku supports 200k tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.

Which is cheaper, Claude 3.5 Haiku or Step 3.5 Flash?

Step 3.5 Flash is cheaper on tracked token pricing. Claude 3.5 Haiku costs $0.80/1M input and $4/1M output tokens. Step 3.5 Flash costs $0.10/1M input and $0.30/1M output tokens. Provider discounts or batch pricing can still change the final bill.

Is Claude 3.5 Haiku or Step 3.5 Flash open source?

Claude 3.5 Haiku is listed under Unknown. Step 3.5 Flash is listed under Open Source. 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, Claude 3.5 Haiku or Step 3.5 Flash?

Claude 3.5 Haiku has the clearer documented vision signal in this comparison. If vision is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Which is better for reasoning mode, Claude 3.5 Haiku or Step 3.5 Flash?

Both Claude 3.5 Haiku and Step 3.5 Flash expose reasoning mode. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface.

Where can I run Claude 3.5 Haiku and Step 3.5 Flash?

Claude 3.5 Haiku is available on Anthropic, OpenRouter, AWS Bedrock, GCP Vertex AI, and Replicate API. Step 3.5 Flash is available on OpenRouter. 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.