Which is cheaper, Claude 3.5 Sonnet or Step-3.5-Flash?
As of August 20, 2026, Step-3.5-Flash is 97% cheaper on blended LLM API pricing. Step-3.5-Flash costs $0.10 per million input tokens and $0.40 per million output tokens ($0.50 blended 1M-in + 1M-out). Claude 3.5 Sonnet costs $3.00 / $15.00 per million tokens ($18.00 blended). Sources: https://platform.claude.com/docs/en/about-claude/pricing and https://anotherwrapper.com/tools/llm-pricing. The cheapest LLM for your app still depends on how many output tokens you generate.
How much does Claude 3.5 Sonnet vs Step-3.5-Flash cost per million tokens?
Claude 3.5 Sonnet Claude API pricing from Anthropic is $3.00 input and $15.00 output per million tokens via Anthropic. Step-3.5-Flash StepFun API pricing is $0.10 input and $0.40 output per million tokens via StepFun. Use those four numbers, not ChatGPT Plus or Claude Pro subscription prices, when you are comparing APIs.
Which is better for coding, Claude 3.5 Sonnet or Step-3.5-Flash?
Step-3.5-Flash leads on SWE-bench Verified: Claude 3.5 Sonnet at 49% vs Step-3.5-Flash at 74.4%. SWE-bench measures real GitHub fixes; LiveCodeBench measures contest programming.
What is the context window for Claude 3.5 Sonnet vs Step-3.5-Flash?
Claude 3.5 Sonnet supports a 200K token context window, while Step-3.5-Flash supports 66K tokens. Claude 3.5 Sonnet offers a larger context window. Filling a larger window bills more input tokens, so the cheaper-per-million model can still cost more on long documents.
Which model performs better on benchmarks, Claude 3.5 Sonnet or Step-3.5-Flash?
Step-3.5-Flash leads on 2 of 2 shared benchmarks versus Claude 3.5 Sonnet's 0 wins. Check the comparison table for GPQA Diamond, SWE-bench, MMLU, HLE, and the other evals we track. Token price and benchmark score together are the usual LLM comparison, not either number alone.
Is Claude 3.5 Sonnet or Step-3.5-Flash better for production use?
Both Claude 3.5 Sonnet and Step-3.5-Flash are production API models. For cost-sensitive production traffic, Step-3.5-Flash has better economics on the blended 1M-in + 1M-out scale. For maximum capability, weight the benchmark table for your domain. Many production stacks route cheap models for drafts and a frontier model for the hard turn, which is usually cheaper than sending everything to the expensive API.
Can I switch between Claude 3.5 Sonnet and Step-3.5-Flash in my app?
Yes. Call Claude 3.5 Sonnet through Anthropic and Step-3.5-Flash through StepFun with separate API keys, or through a gateway that already wraps both. Keep prompts in tokens, not characters, when you estimate the invoice. AnotherWrapper templates can swap providers without rewriting auth and billing.
How accurate is this Claude 3.5 Sonnet vs Step-3.5-Flash pricing data?
List rates are the latest published Claude API pricing from Anthropic and StepFun API pricing, quoted per million tokens. Official rate sheets: https://platform.claude.com/docs/en/about-claude/pricing and https://anotherwrapper.com/tools/llm-pricing. Prompt caching, batch APIs, and committed-use discounts can change the invoice. Benchmark scores are from official publications and independent evals, updated as new numbers land.
What is the output token limit for Claude 3.5 Sonnet and Step-3.5-Flash?
Claude 3.5 Sonnet supports up to 200K output tokens per request, while Step-3.5-Flash supports up to 8K output tokens. Output tokens are usually the expensive half of API pricing, so a higher max output cap is a capability, not a discount.
Which model has better throughput, Claude 3.5 Sonnet or Step-3.5-Flash?
Claude 3.5 Sonnet runs at approximately 78 tokens/second while Step-3.5-Flash runs at 150 tokens/second. Step-3.5-Flash is faster in raw throughput. Throughput (tokens per second) and time-to-first-token are why two models with the same per-million-token price can still feel different in chat and agents.
How do I switch the models in this Claude 3.5 Sonnet vs Step-3.5-Flash comparison?
Use the model pickers at the top of this LLM comparison. Search any model in the index and the URL updates. Open Claude 3.5 Sonnet or Step-3.5-Flash from the sidebar for the single-model API pricing page, or go back to the LLM pricing table to sort by cheapest blended cost.
