GPT 5.3 Codex Review
GPT 5.3 Codex Review is served by 1 provider that kRouter can route to, with a 400K-token context window and pricing from $6.00 per 1M input tokens. Routing through kRouter means any OpenAI-compatible tool can reach it, with failover to another model if the provider is rate limited.
How to route to GPT 5.3 Codex Review
| Provider | Route as |
|---|---|
| OpenAI Codex | cx/gpt-5.3-codex-review |
What GPT 5.3 Codex Review is suited for
A 400K window is large enough to hold a substantial part of a codebase in one turn, so it suits whole-repo refactors and long agent sessions where the history keeps growing. It supports extended reasoning, which helps on debugging and multi-step planning but spends output tokens on thinking before the answer appears — worth knowing when you set max_tokens. Tool and function calling are supported, so it can drive an agent loop. Cached input is billed at $3.00 against $6.00 fresh, which is the difference that matters most for agent work — the same context is resent on every turn.
Specs
- Context window
- 400K
- Max output
- 128K
- Input / 1M
- $6.00
- Output / 1M
- $24.00
- Extended reasoning
- Tool / function calling
Cheaper alternatives to GPT 5.3 Codex Review
Comparable capabilities at a lower rate. With a kRouter combo you can send routine turns to one of these and reserve GPT 5.3 Codex Review for the work that actually needs it.
- Claude Opus 4.6$5.00 in · $25.00 out per 1M
- Claude Opus 4.7$5.00 in · $25.00 out per 1M
- GPT-5.2$5.00 in · $20.00 out per 1M
- GPT-5.2 Codex$5.00 in · $20.00 out per 1M
GPT 5.3 Codex Review FAQ
How much does GPT 5.3 Codex Review cost?
GPT 5.3 Codex Review is $6.00 per 1M input tokens and $24.00 per 1M output tokens. Cached input is $3.00, which matters a lot for agent work that resends the same context each turn.
Which providers serve GPT 5.3 Codex Review?
OpenAI Codex serves it. kRouter routes to it as cx/gpt-5.3-codex-review.
What is GPT 5.3 Codex Review's context window?
400K tokens, with up to 128K tokens of output. kRouter publishes this on /v1/models as context_length, so clients read the real number instead of guessing from the model name.
Is there a cheaper alternative to GPT 5.3 Codex Review?
Yes — Claude Opus 4.6 ($5.00/1M in), Claude Opus 4.7 ($5.00/1M in), GPT-5.2 ($5.00/1M in), GPT-5.2 Codex ($5.00/1M in) are cheaper with comparable capabilities. A kRouter combo can send routine turns to one of those and keep GPT 5.3 Codex Review for the work that needs it.
Route to GPT 5.3 Codex Review from any tool
kRouter runs locally and gives Claude Code, Cursor, Codex and the rest one endpoint that reaches every provider above — with automatic failover. Free and MIT-licensed.
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