Pricing
Codex Credits Explained: What They Cost, How Fast They Burn, and When They Expire
OpenAI doesn't publish a per-credit price for Codex. What credits do, the 2,500-credit student grant, Fast mode multipliers, and when to buy or upgrade.
5 min read
Credit rules checked Oct 24, 2026 in OpenAI’s credits help article; other dates under Sources. No affiliate links (how we work).
Codex credits cost whatever OpenAI shows you at checkout, because there’s no public per-credit price. Codex pricing says “Credit purchase prices and applicable discounts depend on your plan or agreement” (verified Oct 21, 2026), and the help center says amounts and prices “can vary by account, region, and plan” (verified Oct 24, 2026).
OpenAI does publish how fast credits burn, who can buy them and when they expire. For plans and limits, see Codex pricing.
The short answer
- Price: not published. Check the Add credits screen on your own account.
- Expiry: “valid for 12 months from purchase”, then gone.
- Burn: Fast mode costs 2x credits, Ultrafast 6x.
- Free credits: verified US and Canadian university students get 2,500.
We haven’t bought Codex credits; facts come from OpenAI’s pages. Other tools: AI coding tools compared.
What a Codex credit is worth in dollars
The only dollar figure OpenAI attaches to credits is on its students page: the grant shows as “2,500 credits, which is equivalent to $100” (verified Oct 21, 2026). That’s one promotional offer’s value, not a store price.
Until checkout, credits are Schrute Bucks: you know how many you have, not what they’re worth in Stanley nickels.
How fast credits burn
Credits are charged per token at published per-model rates: GPT-6.1 Sol is 50 credits per 1M input tokens and 250 per 1M output. OpenAI’s own example: “A typical GPT-5.6 Sol task may use 2-15 credits” (verified Oct 21, 2026). The full rate table is in Codex pricing.
Speed costs extra, and the multipliers aren’t the same for credits as for your plan:
| Mode | Credits | Plan usage |
|---|---|---|
| Fast | 2x | 2.5x |
| Ultrafast | 6x | 8x |
Credits column: “Purchased credits and Enterprise pay-as-you-go usage”; plan column: included subscription usage (verified Oct 21, 2026). One catch on Pro: “At launch, buying credits on Pro 100 or Pro 200 does not unlock Ultrafast” (verified Oct 21, 2026).
Who can buy credits
- Plus and Pro: “ChatGPT Plus and Pro users who reach their usage limit can purchase additional credits” (verified Oct 21, 2026).
- Business, Edu, Enterprise: flexible-pricing workspaces “can purchase additional workspace credits”.
- Free and Go: “currently available to a limited group”. If you don’t see Add credits, you can’t buy yet (verified Oct 24, 2026).
- Anyone: extra local chats “using an API key”, at API prices.
Included usage goes first, then credits, and one balance also covers ChatGPT Work, Word, Excel and PowerPoint. They “are not API credits” (verified Oct 24, 2026).
Free Codex credits for students
“Verified university students in the United States and Canada can claim $100 in ChatGPT credits to use in Codex. One offer per student.” They “expire 12 months after the grant date”, aren’t API credits, and need a ChatGPT Free, Go, Plus or Pro account. There’s no discounted student plan, only the credits (verified Oct 21, 2026). It’s US and Canada only, which is a shame for everyone else.
How to check your balance, and when credits expire
Balance: Settings > Usage in ChatGPT, or Usage & Billing in the Codex app. That’s also where you buy credits and turn on automatic reload, which tops you back up to a target balance, capped by a monthly spend limit you set (verified Oct 24, 2026).
Expiry: “Credits are valid for 12 months from purchase. Unused credits expire and do not roll over after the expiry date.” They’re non-refundable except in listed cases, and non-transferable (verified Oct 24, 2026).
Negative balance: a task that outlasts your balance can push it below zero; your next purchase pays that off first. Unpublished pricing that can dip into debt sounds like a Kendall Roy earnings call.
Credits vs upgrading to Pro
Plus is $20/mo; Pro is $100, $200 or $500/mo (verified Oct 19, 2026). With no per-credit price and no Pro usage multiples published, there’s no honest break-even number. Think in situations:
- You run out once or twice a month: credits. You pay only for the overflow, and they last 12 months.
- You run out most weeks: a bigger plan. Pro plans “currently have no five-hour limit” (verified Oct 19, 2026), and Pro 500 is the only Pro tier with Ultrafast included.
- You want a hard ceiling: an API key with your own spend controls.
Still unsure? See Codex vs Claude Code, Codex alternatives, the Codex price tracker and ChatGPT Plus cost.
Here’s what I’d do
On Plus, I’d open Add credits the first time I hit the limit, see my price, and buy the smallest amount. Back more than twice in a month? I’d price up Pro instead. And I’d keep Fast mode off on credits, because 2x adds up quietly.
Buying credits most weeks? Codex Pro vs Plus shows when upgrading beats topping up.
Not paying yet? Is Codex free? covers which ChatGPT plans include Codex.
Credits burn at different rates per model. GPT-6.1 Sol vs Terra lists what each model costs in Codex credits.
Deciding between Business seats and Pro for heavy Codex use? See Codex Business vs Pro.
Cloud tasks failing with a timeout before they use any credits? The Codex error creating task fix lists the reported causes.
FAQ
How much do Codex credits cost? OpenAI doesn’t publish a per-credit price; it depends on your plan, account and region and shows at checkout.
How many tokens is a Codex credit? It depends on the model; OpenAI publishes credits per 1M tokens, e.g. GPT-6.1 Sol is 50 input and 250 output credits per 1M.
Do Codex credits expire? Yes, purchased credits are valid for 12 months from purchase and student credits expire 12 months after the grant date.
Can students get free Codex credits? Verified US and Canadian university students can claim 2,500 credits, which OpenAI says equals $100, once per student.
Is it cheaper to buy credits or upgrade? Credits suit occasional overflow; if you run out most weeks, upgrade instead.
Sources
- OpenAI Help, Using credits for flexible usage (balance, expiry, refunds, access): https://help.openai.com/en/articles/12642688-using-credits-for-flexible-usage-in-chatgpt-personal-plans (verified 2026-10-24)
- OpenAI, Codex pricing (plans, multipliers, credit rates): https://developers.openai.com/codex/pricing (verified 2026-10-19 and 2026-10-21)
- OpenAI Help, About ChatGPT Pro plans (Ultrafast by tier): https://help.openai.com/en/articles/9793128-about-chatgpt-pro-plans (verified 2026-10-21)
- OpenAI, Codex for students: https://developers.openai.com/community/students (verified 2026-10-21)