Codex Credits Calculator
Codex meters usage in credits worth $0.04 each, exactly OpenAI's direct API dollar rate multiplied by 25. Estimate GPT-5.6 Sol, Terra, and Luna credit burn for your workload, and see that it costs the same as calling the API yourself. Everything runs in your browser.
Runs entirely in your browser. Nothing you enter leaves this page.
Rates verified against OpenAI's published Codex credit and API rate cards on 2026-07-21.
Codex credits are OpenAI's usage-based billing unit for Codex, in force since 2026-04-02. One credit costs $0.04, and the credit rate card equals OpenAI's direct API dollar rate card multiplied by 25 for every model, so there is no per-model markup. GPT-5.6 usage averages 5 to 40 credits per message. OpenAI publishes no fixed monthly credit allotment: plans meter usage in a shared 5-hour window plus weekly limits. Rates verified on 2026-07-21.
Comparing platforms? See how Codex credits stack up against GitHub Copilot's AI credits, or browse LLM pricing across providers.
Your usage
Estimated burn
- Credits per request
- 6.6
- $0.26
- Credits per month
- 2,893
Codex credits are OpenAI API pricing repackaged. 1 credit = $0.04, and this workload costs the SAME as calling the API directly ($115.72).
Billed in credits
$115.72
Direct API, same tokens
$115.72
0% markup versus the direct OpenAI API. Credits are API list pricing metered in a different unit.
GPT-5.6 usage averages 5 to 40 credits per message, and Codex plans carry no fixed monthly credit allotment: Codex moved from per-message pricing to token-based credits on 2026-04-02 (Enterprise 2026-04-23). Plans meter local messages and cloud chats in a shared 5-hour window plus weekly limits. OpenAI publishes no fixed monthly credit allotment per plan, so this dataset carries none.
Credit rate card vs. direct API rate card
Credits per 1 million tokens next to OpenAI's direct API dollars per 1 million tokens. At $0.04 per credit the two columns always land on the same dollar figure, model for model, which is the proof that Codex credits carry no markup.
| Model | Credits in / 1M | Credits out / 1M | API $ in / 1M | API $ out / 1M |
|---|---|---|---|---|
| GPT-5.6 Sol | 125 | 750 | $5.00 | $30.00 |
| GPT-5.6 Terra | 63 | 375 | $2.50 | $15.00 |
| GPT-5.6 Luna | 25 | 150 | $1.00 | $6.00 |
| GPT-5.4 mini | 19 | 113 | $0.75 | $4.50 |
GPT-5.5 and GPT-5.4 are prior-generation duplicates of Sol and Terra at identical rates, still selectable in the calculator above. Cached input bills at one tenth of the fresh input rate on every tier.
Frequently asked questions
What is a Codex credit?
A Codex credit is OpenAI's token-metered billing unit for Codex, in force since April 2, 2026. One credit is worth $0.04, and the Codex credit rate card equals the OpenAI API dollar rate card multiplied by 25 for every model, so credits are simply API list pricing in a different unit, with no per-model markup.
How many credits does a Codex task use?
OpenAI states GPT-5.6 usage averages 5 to 40 credits per message, and fast mode consumes more. The exact figure depends on the model and the tokens in the request: enter your model and a token workload above to see credits per request, per day, and per month.
Are Codex credits cheaper than calling the API directly?
No, they are the same. At $0.04 per credit the Codex credit card equals the OpenAI API dollar card exactly (GPT-5.6 Sol input is 125 credits per 1M tokens, which is $5.00, the API rate). There is no discount and no markup; you pay API list pricing, metered in credits.
Which GPT-5.6 tier uses the fewest credits?
Luna is the cheapest at 25 credits per 1M input and 150 per 1M output ($1 / $6). Terra is 62.5 / 375 ($2.50 / $15). Sol, the flagship, is 125 / 750 ($5 / $30). Luna costs one fifth of Sol per token, so for the same workload Luna burns one fifth of the credits.
Do Codex plans include a set monthly credit allowance?
No. OpenAI publishes no fixed monthly credit allotment for Codex. ChatGPT Plus and Pro meter local messages and cloud chats in a shared 5-hour window plus weekly limits, and both can purchase extra credits. Business and Enterprise use flexible pricing that can buy additional workspace credits.
How does a Codex credit compare to a GitHub Copilot AI credit?
They are different unit sizes for the same idea. One Codex credit is $0.04 and one GitHub Copilot AI credit is $0.01, so one Codex credit equals four Copilot credits. Both meter direct API rates, so for the same model and workload the dollar cost is identical; only the credit count differs.
Sources
Prices last verified 2026-07-21, from each provider's official page.
- OpenAI: ChatGPT and Codex plans and pricing (credit rate card)
- OpenAI API pricing (direct dollar rates)
This is an independent community tool, not affiliated with OpenAI. Estimates only; your bill is computed by OpenAI. Per-request token counts here are your estimates, not measurements. Rates change as models change, so check the sources for current numbers.
