Step 3.7 Flash vs GPT-5.5 Pro: side-by-side summary

Step 3.7 Flash and GPT-5.5 Pro are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.

Step 3.7 Flash, from stepfun, has a 262,144-token context window and is priced at $0.16/M tokens input, $0.92/M tokens output on OpenRouter.

GPT-5.5 Pro, from OpenAI, has a 1,050,000-token context window and is priced at $30/M tokens input, $180/M tokens output on OpenRouter.

Context window

• Step 3.7 Flash: 262,144 tokens
• GPT-5.5 Pro: 1,050,000 tokens

Price

• Step 3.7 Flash: $0.16/M tokens input, $0.92/M tokens output
• GPT-5.5 Pro: $30/M tokens input, $180/M tokens output

Provided by

• Step 3.7 Flash: stepfun
• GPT-5.5 Pro: OpenAI

• Step 3.7 Flash model details, providers and pricing
• GPT-5.5 Pro model details, providers and pricing