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OpenAI·Text60%+ off vs official

GPT-5.3 CodexAPI

OpenAI GPT-5.3 Codex — coding-specialized.

Input price

$0.70

per 1M tokens

Output price

$5.60

per 1M tokens

Prompt caching

Pass cache_control on a stable prefix and cache hits bill at a fraction of input. Cache writes bill at the plain input rate.

Cache read
$0.14

Auto-derived from input × 0.2

Specs

Model ID
gpt-5-3-codex
Endpoint
POST /v1/chat/completions
Category
Text
Provider
OpenAI
Capabilities
functionstreamingthinkinglong-context

Drop-in OpenAI compatibility

Point your existing OpenAI SDK at api.kunavo.com/v1 and swap the model id. No streaming changes, no SDK changes.

View docsGPT API pricing guide

Try it

Set KUNAVO_API_KEY from /app/keys, then run any of the snippets below.

curl
curl https://api.kunavo.com/v1/chat/completions \
  -H "Authorization: Bearer $KUNAVO_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-5-3-codex",
    "messages": [
      {"role": "user", "content": "Hello, GPT-5.3 Codex"}
    ],
    "stream": false
  }'

Kunavo vs calling OpenAI directly

Same GPT-5.3 Codex weights, same responses. What a gateway changes is the account, the SDK and the bill — here is the honest side-by-side.

KunavoOpenAI direct
Price (per 1M tokens)$0.70 / $5.60 (−60%)$1.75 / $14.00
AccountOne Kunavo account, key in 2 minutes, $5 minimum top-upA OpenAI account plus its own billing setup
SDKKeep the OpenAI SDK — change base_url, set model to "gpt-5-3-codex"OpenAI's SDK, or their OpenAI-compatible layer where offered
Same key also reachesClaude, Gemini, GPT, image, video and audio modelsOpenAI's own catalog only
BillingOne Stripe balance, pay-as-you-go, never expires; failed requests unbilledA separate invoice per provider
Rate limitsShared gateway capacity, no contractual per-account limitOpenAI's own tier limits, raised by usage history or contract

Go direct to OpenAI when you need a contractual rate limit, an enterprise SLA, or a provider-only feature on day one. Use Kunavo when you want one key, one bill and a lower per-token rate across every provider.

FAQ

How much does GPT-5.3 Codex cost?

On Kunavo, GPT-5.3 Codex is $0.70 per 1M input tokens and $5.60 per 1M output tokens — about 60% under OpenAI's official price. Failed requests are never billed, and it's pay-as-you-go — you only pay for successful calls.

Can I call GPT-5.3 Codex with the OpenAI SDK?

Yes. Set base_url to https://api.kunavo.com/v1, pass your Kunavo key, and set model to "gpt-5-3-codex". Requests and responses are OpenAI-compatible.

What endpoint does GPT-5.3 Codex use?

GPT-5.3 Codex is called via POST /v1/chat/completions on Kunavo's OpenAI-compatible API.

What is GPT-5.3 Codex good for?

GPT-5.3 Codex is a text model from OpenAI, with support for function, streaming, thinking, long-context.

What is different from calling OpenAI directly?

The model is the same, at about 60% under OpenAI's list price. What changes is around it: one key and one Stripe balance instead of a OpenAI account with its own billing, the OpenAI SDK with base_url swapped instead of a provider-specific SDK, and the same key also reaching Claude, Gemini, GPT, image, video and audio models. The tradeoff is that gateway capacity is shared — if you need a contractual rate limit or an enterprise SLA on GPT-5.3 Codex specifically, go direct to OpenAI.

Is GPT-5.3 Codex cheaper on Kunavo?

Yes — GPT-5.3 Codex is about 60% under OpenAI's official list price on Kunavo, with no subscription and no minimum monthly spend. You pay per token from a $5 top-up, failed requests are never billed, and the balance never expires.

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