GPT-5.1-Codex-Mini vs Riverflow V2 Fast: side-by-side summary

GPT-5.1-Codex-Mini and Riverflow V2 Fast are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.

GPT-5.1-Codex-Mini, from OpenAI, has a 400,000-token context window and is priced at $0.25/M tokens input, $2/M tokens output on OpenRouter.

Riverflow V2 Fast, from Sourceful, has a 8,192-token context window and is priced from $0.02/image on OpenRouter.

Context window

• GPT-5.1-Codex-Mini: 400,000 tokens
• Riverflow V2 Fast: 8,192 tokens

Price

• GPT-5.1-Codex-Mini: $0.25/M tokens input, $2/M tokens output
• Riverflow V2 Fast: from $0.02/image

Provided by

• GPT-5.1-Codex-Mini: OpenAI
• Riverflow V2 Fast: Sourceful

• GPT-5.1-Codex-Mini model details, providers and pricing
• Riverflow V2 Fast model details, providers and pricing