Pick a winner in each dimension — change your vote anytime.
Pricing and capabilities synced from the OpenRouter catalogue. Scores are editorial (0–10).
Choose DeepSeek V4 Flash if you want cheap, high-volume open-weight agent steps. Choose GPT-5.3-Codex if you want codex CLI users and dedicated coding agents.
In our editorial scoring, DeepSeek V4 Flash leads in 3 of five dimensions (speed, value for $ and reliability), while GPT-5.3-Codex leads in 2. On price, DeepSeek V4 Flash runs about $0.12 per 1M tokens (blended) and is open-weight; GPT-5.3-Codex is about $5.42 and proprietary.
The model picks the moves; the agent runs the loop, the tools, and the guardrails. Once you've chosen a model, see which agent gets the most out of it.