Model Comparison

Claude 3.5 Sonnet vs Step-3.5-Flash

Comparing Claude 3.5 Sonnet and Step-3.5-Flash across benchmarks, pricing, and capabilities.

Want to compare interactively?Try the playground

Performance Benchmarks

Comparative analysis across standard metrics

No common benchmarks found

Claude 3.5 Sonnet and Step-3.5-Flash don't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

Step-3.5-Flash costs less

For input processing, Claude 3.5 Sonnet ($3.00/1M tokens) is 30.0x more expensive than Step-3.5-Flash ($0.10/1M tokens).

For output processing, Claude 3.5 Sonnet ($15.00/1M tokens) is 37.5x more expensive than Step-3.5-Flash ($0.40/1M tokens).

In conclusion, Claude 3.5 Sonnet is more expensive than Step-3.5-Flash.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Fri Apr 17 2026 • llm-stats.com
Anthropic
Claude 3.5 Sonnet
Input tokens$3.00
Output tokens$15.00
Best providerAWS Bedrock
StepFun
Step-3.5-Flash
Input tokens$0.10
Output tokens$0.40
Best providerStepFun
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Claude 3.5 Sonnet accepts 200,000 input tokens compared to Step-3.5-Flash's 65,536 tokens. Claude 3.5 Sonnet can generate longer responses up to 200,000 tokens, while Step-3.5-Flash is limited to 8,192 tokens.

Anthropic
Claude 3.5 Sonnet
Input200,000 tokens
Output200,000 tokens
StepFun
Step-3.5-Flash
Input65,536 tokens
Output8,192 tokens
Fri Apr 17 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Claude 3.5 Sonnet supports multimodal inputs, whereas Step-3.5-Flash does not.

Claude 3.5 Sonnet can handle both text and other forms of data like images, making it suitable for multimodal applications.

Claude 3.5 Sonnet

Text
Images
Audio
Video

Step-3.5-Flash

Text
Images
Audio
Video

License

Usage and distribution terms

Claude 3.5 Sonnet is licensed under a proprietary license, while Step-3.5-Flash uses Apache 2.0.

License differences may affect how you can use these models in commercial or open-source projects.

Claude 3.5 Sonnet

Proprietary

Closed source

Step-3.5-Flash

Apache 2.0

Open weights

Release Timeline

When each model was launched

Claude 3.5 Sonnet was released on 2024-06-21, while Step-3.5-Flash was released on 2026-02-02.

Step-3.5-Flash is 20 months newer than Claude 3.5 Sonnet.

Claude 3.5 Sonnet

Jun 21, 2024

1.8 years ago

Step-3.5-Flash

Feb 2, 2026

2 months ago

1.6yr newer

Knowledge Cutoff

When training data ends

Neither model specifies a knowledge cutoff date.

Unable to compare the recency of their training data.

No cutoff dates available

Provider Availability

Claude 3.5 Sonnet is available from Bedrock, Google. Step-3.5-Flash is available from StepFun.

Claude 3.5 Sonnet

bedrock logo
AWS Bedrock
Input Price:Input: $3.00/1MOutput Price:Output: $15.00/1M
google logo
Google
Input Price:Input: $3.00/1MOutput Price:Output: $15.00/1M

Step-3.5-Flash

stepfun logo
StepFun
Input Price:Input: $0.10/1MOutput Price:Output: $0.40/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Anthropic
Larger context window (200,000 tokens)
Supports multimodal inputs
StepFun
Less expensive input tokens
Less expensive output tokens
Has open weights
AnthropicClaude 3.5 Sonnet
StepFunStep-3.5-Flash
Compare in Playground

Detailed Comparison

AI Model Comparison Table
Feature
Anthropic
Claude 3.5 Sonnet
StepFun
Step-3.5-Flash

FAQ

Common questions about Claude 3.5 Sonnet vs Step-3.5-Flash

Claude 3.5 Sonnet (Anthropic) and Step-3.5-Flash (StepFun) each have strengths in different areas. Compare their benchmark scores, pricing, context windows, and capabilities above to determine which fits your needs.
Claude 3.5 Sonnet scores GSM8k: 96.4%, BIG-Bench Hard: 93.1%, HumanEval: 92.0%, MGSM: 91.6%, MMLU: 90.4%. Step-3.5-Flash scores AIME 2025: 97.3%, Tau-bench: 88.2%, LiveCodeBench v6: 86.4%, IMO-AnswerBench: 85.4%, SWE-Bench Verified: 74.4%.
Step-3.5-Flash is 30.0x cheaper for input tokens. Claude 3.5 Sonnet costs $3.00/M input and $15.00/M output via bedrock. Step-3.5-Flash costs $0.10/M input and $0.40/M output via stepfun.
Claude 3.5 Sonnet supports 200K tokens and Step-3.5-Flash supports 66K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.
Key differences include context window (200K vs 66K), input pricing ($3.00 vs $0.10/M), multimodal support (yes vs no), licensing (Proprietary vs Apache 2.0). See the full comparison above for benchmark-by-benchmark results.
Claude 3.5 Sonnet is developed by Anthropic and Step-3.5-Flash is developed by StepFun.