OpenAI: GPT-5.3-Codex

OpenAI

openai/gpt-5.3-codex

GPT-5.3-Codex is OpenAI’s most advanced agentic coding model, combining the frontier software engineering performance of GPT-5.2-Codex with the broader reasoning and professional knowledge capabilities of GPT-5.2. It achieves state-of-the-art results...

Context

400K

Input /1M

$1.75

Output /1M

$14.00

Latency (TTFT)

904ms

Pricing

Per 1M tokens, in USD

Input$1.75

Output$14.00

Cache read$0.175

Specs

text inimage infile intext outModerated

TokenizerGPT

Max output tokens128,000

Supported parameters

include_reasoningmax_completion_tokensmax_tokensreasoningreasoning_effortresponse_formatseedstructured_outputstool_choicetools

Where it ranks on price

Against 157 routable models

Input$1.75

Cheaper than 24% of routable models

Output$14.00

Cheaper than 12% of routable models

Benchmarks

No third-party benchmark data available for this model yet.

Call this model

Swap in your Mizan key — the request/response bodies are OpenAI chat-completion shaped.

cURL

curl https://api.app-mizan.com/v1/chat/completions \
  -H "Authorization: Bearer mizan_rt_..." \
  -H "Content-Type: application/json" \
  -d '{
    "model": "openai/gpt-5.3-codex",
    "messages": [{ "role": "user", "content": "Say hi in five words." }]
  }'

Models

OpenAI: GPT-5.3-Codex

OpenAI

openai/gpt-5.3-codex

GPT-5.3-Codex is OpenAI’s most advanced agentic coding model, combining the frontier software engineering performance of GPT-5.2-Codex with the broader reasoning and professional knowledge capabilities of GPT-5.2. It achieves state-of-the-art results...

Context

400K

Input /1M

$1.75

Output /1M

$14.00

Latency (TTFT)

904ms

Pricing

Per 1M tokens, in USD

Input$1.75

Output$14.00

Cache read$0.175

Specs

text inimage infile intext outModerated

TokenizerGPT

Max output tokens128,000

Supported parameters

include_reasoningmax_completion_tokensmax_tokensreasoningreasoning_effortresponse_formatseedstructured_outputstool_choicetools

Where it ranks on price

Against 157 routable models

Input$1.75

Cheaper than 24% of routable models

Output$14.00

Cheaper than 12% of routable models

Benchmarks

No third-party benchmark data available for this model yet.

Call this model

Swap in your Mizan key — the request/response bodies are OpenAI chat-completion shaped.

cURL

curl https://api.app-mizan.com/v1/chat/completions \
  -H "Authorization: Bearer mizan_rt_..." \
  -H "Content-Type: application/json" \
  -d '{
    "model": "openai/gpt-5.3-codex",
    "messages": [{ "role": "user", "content": "Say hi in five words." }]
  }'