Codex 28-day program: every reset and update, day by day
Data as of · Vendor check: dated on each entry · Page updated
Short answer (as of 30 Oct 2026): OpenAI’s 28-day Codex program has had 12 usage resets (1 banked for paid accounts, 11 global) and 4 logged updates that were not a reset, by SGT announcement date. It runs to Day 28, Sun 1 Nov 2026 US Pacific (Mon 2 Nov 2026 SGT). Each row links the change-log entry it comes from.
PlanYield, 'Codex 28-day program: every reset and update, day by day', updated 31 Oct 2026, https://planyield.dev/limits/codex/28-day-program/
Day-by-day ledger
Program entry: Codex 28-day program of daily improvements or usage resets, from a post by OpenAI’s Codex lead on 5 Oct 2026 (SGT). Ends: Day 28, Sun 1 Nov 2026 US Pacific (Mon 2 Nov 2026 SGT). After that, each plan’s own limits apply, as its row shows.
| Day | Date (SGT) | What happened | Status | Source · entry |
|---|---|---|---|---|
| Day 2 | Usage reset | Reset (global) | Vendor post on X x.com ↗entry updated | |
| Day 3 | Banked usage reset for paid accounts | Reset (banked, paid accounts) | Vendor post on X x.com ↗entry updated | |
| Day 6 | Usage reset | Reset (global) | Vendor post on X x.com ↗entry updated | |
| Day 8 | Usage reset | Reset (global) | Vendor post on X x.com ↗entry updated | |
| Day 10 | Usage reset | Reset (global) | Vendor post on X x.com ↗entry updated | |
| Day 13 | Usage reset | Reset (global) | Vendor post on X x.com ↗entry updated | |
| Day 15 | Usage reset | Reset (global) | Vendor post on X x.com ↗entry updated | |
| Day 16 | Codex keeps prompt cache indefinitely; API adds 12h caching | Update, not a reset | Vendor post on X x.com ↗entry updated | |
| Day 17 | Codex Day 17 is a usage reset, the eighth of the program | Reset (global) | Vendor post on X x.com ↗entry updated | |
| Day 18 | Codex Day 18 is a usage reset, the ninth of the program | Reset (global) | Vendor post on X x.com ↗entry updated | |
| Day 19 | Small updates | Update, not a reset | Vendor post on X x.com ↗entry updated | |
| Day 20 | Codex Day 20 is a usage reset, the tenth of the program | Reset (global) | Vendor post on X x.com ↗entry updated | |
| Day 21 | Codex Day 21 is a usage reset, the eleventh of the program | Reset (global) | Vendor post on X x.com ↗entry updated | |
| Day 22 | GPT-6.1 Terra launches in Codex with about 2x Sol's usage | Update, not a reset | Vendor page openai.com ↗entry updated | |
| Day 23 | Codex Day 23 is a usage reset, the twelfth of the program | Reset (global) | Vendor post on X x.com ↗entry updated | |
| Day 25 | OpenAI doubles ChatGPT Pro and Business Premium limits; Pro 200 cut cancelled | Update, not a reset | Vendor post on X x.com ↗entry updated |
Every Codex entry logged during the program
Dates are in SGT. A day number is shown when the entry names it.
- : Approve for me auto-review no longer counts against Codex usage
- : GPT-5.5 leaves Codex ChatGPT sign-in
- Day 16, : Codex keeps prompt cache indefinitely; API adds 12h caching
- : OpenAI fixes Codex accounts metered against the wrong plan
- Day 17, : Codex Day 17 is a usage reset, the eighth of the program
- Day 18, : Codex Day 18 is a usage reset, the ninth of the program
- Day 20, : Codex Day 20 is a usage reset, the tenth of the program
- Day 21, : Codex Day 21 is a usage reset, the eleventh of the program
- Day 22, : GPT-6.1 Terra launches in Codex with about 2x Sol's usage
- Day 23, : Codex Day 23 is a usage reset, the twelfth of the program
- : ChatGPT Pro and Business add monthly OpenAI API credits
- Day 25, : OpenAI doubles ChatGPT Pro and Business Premium limits; Pro 200 cut cancelled
Recent changes
- OpenAI doubles ChatGPT Pro and Business Premium limits; Pro 200 cut cancelled Vendor post on X
- ChatGPT Pro and Business add monthly OpenAI API credits Vendor page
- Codex Day 23 is a usage reset, the twelfth of the program Vendor post on X
- GPT-6.1 Terra launches in Codex with about 2x Sol's usage Vendor page
- Codex Day 21 is a usage reset, the eleventh of the program Vendor post on X
- Codex Day 20 is a usage reset, the tenth of the program Vendor post on X
More: Codex usage limits · All Codex plans and changes · Program entry · How to check your usage
Plans: ChatGPT Free · ChatGPT Go · ChatGPT Plus · ChatGPT Pro · ChatGPT Business
Dataset licence: CC BY 4.0.
FAQ
How many usage resets has the Codex 28-day program had?
12 as of 30 Oct 2026, by SGT announcement date: 7 Oct, 8 Oct, 11 Oct, 13 Oct, 15 Oct, 18 Oct, 20 Oct, 22 Oct, 23 Oct, 25 Oct, 26 Oct, and 28 Oct. 8 Oct was a banked reset added to paid accounts; the others were global.
When does the Codex 28-day program end?
On Day 28, Sun 1 Nov 2026 US Pacific (Mon 2 Nov 2026 SGT), per OpenAI’s Codex lead. After that, each plan’s own limits apply, as its row shows.
Which program days were not resets?
Day 16 (21 Oct): Codex keeps prompt cache indefinitely; API adds 12h caching; Day 19 (24 Oct): Small updates; Day 22 (27 Oct): GPT-6.1 Terra launches in Codex with about 2x Sol's usage; Day 25 (30 Oct): OpenAI doubles ChatGPT Pro and Business Premium limits; Pro 200 cut cancelled.
Which plans does the program cover?
The posts do not name plans, so PlanYield lists every Codex row: ChatGPT Free, ChatGPT Go, ChatGPT Plus, ChatGPT Pro, and ChatGPT Business.