Codex Plan vs API Cost Calculator
The API (about $85 a month) beats Codex Pro 100 at $100. Codex Plus at $20 is cheaper still, but this much use will likely hit its caps. Change the sliders to match how you use Codex.
The API (about $85 a month) beats Codex Pro 100 at $100. Codex Plus at $20 is cheaper still, but this much use will likely hit its caps.
Plan limits are not published in tokens, so heavy use can hit 5-hour or weekly caps.
| Plan | Price | vs API |
|---|---|---|
| Codex Plus 5-hour + weekly | $20 | saves $65 |
| Codex Pro 100 weekly | $100 | costs $15 more |
| Codex Pro 200 weekly | $200 | costs $115 more |
| Codex Pro 500 weekly | $500 | costs $415 more |
Codex plans vs API at typical usage
| Use | API / mo | Suggested plan | Cheaper |
|---|---|---|---|
| Light chat | $3 | Codex Plus ($20) | API |
| Heavy chat | $25 | Codex Plus ($20) | Plan, saves ~$5 |
| Coding assistant | $85 | Codex Pro 100 ($100) | API |
| Heavy coding agent | $301 | Codex Pro 100 ($100) | Plan, saves ~$201 |
API model: GPT-6.1 Sol, 22 days a month.
Current prices and caps: Codex plans and limits, official pricing.
Assumptions
- Light chat: 15 messages a day, about 2,000 input and 600 output tokens each, 0% of input served from cache.
- Heavy chat: 60 messages a day, about 6,000 input and 1,000 output tokens each, 30% of input served from cache.
- Coding assistant: 120 messages a day, about 20,000 input and 1,500 output tokens each, 60% of input served from cache.
- Heavy coding agent: 500 messages a day, about 40,000 input and 1,200 output tokens each, 85% of input served from cache.
- API cost uses list prices per 1M tokens from our API prices table, with cached input at the cached rate where the provider lists one. No batch discounts or free credits.
- Coding agents resend a lot of context, which is why the agent preset uses large inputs and a high cache share.
- The suggested plan is a rule of thumb: about $45 a month of API usage fits a $20 plan, up to about $320 a month fits a $100 plan, more needs a $200 plan. Vendors do not publish plan limits in tokens, so treat this as a rough guide.
- We compare plans from about $15 a month up, since cheaper tiers often do not include the top model. Team and per seat plans are left out.
- Plans also include apps, tools and features the API does not, and the API has no 5-hour or weekly caps.
FAQ
Is Codex plans cheaper than the API?
For coding assistant use, about 120 messages a day, the same usage on GPT-6.1 Sol costs about $85 a month on the API. The API (about $85 a month) beats Codex Pro 100 at $100. Codex Plus at $20 is cheaper still, but this much use will likely hit its caps.
When is the API cheaper than Codex plans?
For light chat, around 15 short messages a day, the API costs about $3.30 a month, below any paid plan.
Does Codex plans have usage limits?
Yes. See the Codex plans page for the current 5-hour and weekly limits. The API has rate limits but no usage caps.
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See also API prices, best model for the task, plan limits and usage resets.