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OpenAI: GPT-5.3-Codex

openai/gpt-5-3-codex
CompareAPITry this model

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.

Modalities
In / out per 1M$1.75 / $14
Context391K
ReleasedFeb 24, 2026

Providers

3 providers serve this model upstream.

Providers serving this model
ProviderInput /MOutput /MCache read /MLatency P50Throughput P50Uptime
Azure$1.75$14$0.176.39s36 tps100%
OpenAI$1.75$14$0.172.36s63 tps100%
OpenAI$3.50$28$0.351.01s173 tps—

Market-wide measurements, refreshed every 15 minutes. They describe who serves GPT-5.3-Codex in general, not how ProjectCOZY routes your requests.

Pricing

List rates per 1M tokens — what GPT-5.3-Codex costs pay-as-you-go elsewhere, not what you pay here.

Input
$1.75
per 1M tokens
Output
$14
per 1M tokens
Cache read
$0.17
per 1M cached tokens
Included in every pass
GPT-5.3-Codex is included in every ProjectCOZY pass at no extra cost — one flat rate, no per-token metering. The rates above are there for comparison.

Performance

Time to first token and output speed across every provider, over the last 3 days.

0.0s5.0s10.0s15.0s20.0s
Oct 16, 12 AMOct 16, 8 AMOct 16, 4 PMOct 17, 12 AMOct 17, 8 AMOct 17, 4 PMOct 18, 12 AMOct 18, 8 AMOct 18, 4 PMOct 19, 12 AMOct 19, 8 AM
OpenAI Azure
0 tok/s50 tok/s100 tok/s150 tok/s200 tok/s
Oct 16, 12 AMOct 16, 8 AMOct 16, 4 PMOct 17, 12 AMOct 17, 8 AMOct 17, 4 PMOct 18, 12 AMOct 18, 8 AMOct 18, 4 PMOct 19, 12 AMOct 19, 8 AM
OpenAI Azure

Uptime

100% of requests were served successfully over the last 3 days, across all providers.

Last 3 daysAvailability 73.68%
Oct 16, 11:00 AMNow
Availability over the last 24 hoursAvailability 73.11%
100% 83% 67% 50%
Oct 18, 11:50 AMNow

Apps

Tools that most often run GPT-5.3-Codex, by tokens this week.

CodexCli Agent · 57.2% of tokens109.6BFramer31.1% of tokens59.6BItoCloud Agent · 9.8% of tokens18.8BOpenHandsCli Agent · 1.1% of tokens2.1BC3PR0.8% of tokens1.6B

Activity

241.4B tokens processed market-wide in the last month.

020.0B40.0B60.0B80.0B
Sep 19Sep 24Sep 29Oct 4Oct 9Oct 14Oct 19
Tokens

FAQ

Which model id do I use for GPT-5.3-Codex?
openai/gpt-5.3-codex. Send it as the model field from any OpenAI-compatible client, against http://192.168.1.55/v1.
How much context does GPT-5.3-Codex hold?
400,000 tokens per request, of which up to 128,000 can be the response.
What can it accept and return?
Input: text, image, file. Output: text.
What does GPT-5.3-Codex cost on a pass?
Nothing beyond the pass itself. Pay-as-you-go elsewhere it lists at $1.75 per 1M input tokens and $14 per 1M output tokens.
Who built GPT-5.3-Codex?
OpenAI, in the GPT family.

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