Quick answer
The Codex 5-hour limit caps usage in a rolling short window and is the one most people hit during a heavy day. The weekly limit caps total usage across the week and usually decides whether you can keep working on Friday. Both apply at once, so the next available reset is whichever window frees up first.
The two windows, side by side
| Short window | Weekly window | |
|---|---|---|
| Length | About 5 hours, rolling | 7 days |
| What it protects | Burst usage in one sitting | Total usage across the week |
| Typical symptom | A long agent run stops mid-task | Everything stops until the weekly reset |
| Reset behaviour | Capacity returns gradually as the old window ages out | Capacity returns at the weekly reset time |
| Where to check | Usage limits panel in Codex, or UsageAtlas Today | Same panel, second row |
Treat the short window as a rate limit and the weekly window as a budget. A single heavy afternoon can exhaust the short window while barely moving the weekly budget. Three heavy days in a row do the opposite.
Which limit runs out first?
It depends on how you work, but the pattern is predictable:
- Long single sessions with large context and many tool calls burn the 5-hour window first.
- Many short sessions spread across six or seven days burn the weekly window first.
- Switching between models changes the pace. A smaller, cheaper model stretches both windows.
- Parallel agents multiply consumption. Four agents started together can exhaust the short window in one pass.
When a request fails, read the error text. Codex names the window that ran out. That single sentence tells you whether waiting a couple of hours helps or whether you are done until the weekly reset.
Plan around both windows
- Check both rows before starting a large task, not after it fails.
- Keep a cheap model for exploration and a stronger model for the final pass.
- Start new sessions when the context is stale instead of carrying a huge conversation.
- Set an alert at 20% remaining so the short window does not surprise you mid-run.
- When the weekly window is the constraint, move low-value work to another tool or to API billing.
The Codex reset tracker shows when each window returns. If you have already hit one, the Codex usage limit guide lists the fixes that do not involve waiting.
Questions, answered
Does the Codex 5-hour limit reset all at once?
Usually not. A rolling window returns capacity as older usage ages out, so the panel can climb before the full five hours pass. The weekly limit resets at a fixed weekly time.
Can I use the API when the Codex subscription limit runs out?
Yes. API billing is separate from the ChatGPT plan windows. You pay per token instead of drawing on the included allowance.
Do the 5-hour and weekly limits apply to every plan?
They apply to the consumer plans that include Codex. Exact allowances differ by plan and change over time, so check the current numbers in your account rather than trusting a fixed figure.