GPT-5.3 Codex
OpenAI's most capable agentic coding model to date.
Context Window
-
gpt-5.3-codex
Max Output
-
1M tokens
Input
$1.575$1.75
10% off1M tokens
Output
$12.6$14
10% off1M tokens
gpt-5.3-codexPlayground
gpt-5.3-codexNo output yet
Pricing
| Plan | Context Window | Max Output | Input | Output | Cache Write | Cache Read |
|---|---|---|---|---|---|---|
gpt-5.3-codex | - | - | $1.575$1.7510% off 1M tokens | $12.6$1410% off 1M tokens | - | - |
Official OpenAI pricing for GPT-5.3 Codex.
Cached input pricing applies to reused prompt tokens.
README
- OpenAI describes GPT-5.3-Codex as its most capable agentic coding model to date.
- It is optimized for coding tasks in Codex or similar environments, with support for `low`, `medium`, `high`, and `xhigh` reasoning effort settings.
- This model is the best fit for long-running software tasks, agentic code workflows, and products that need a model specialized for implementation rather than general chat.
API
API
Endpoint
POST /v1/responsesAuthentication
Authorization: Bearer YOUR_REACH_API_KEY Content-Type: application/json
Example
curl -X POST "https://direct.reachapi.ai/v1/responses" \
-H "Authorization: Bearer YOUR_REACH_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "YOUR_MODEL_ID",
"input": "Introduce ReachAPI in one sentence.",
"temperature": 0.2
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