On a $20/mo plan doing any sort of agentic coding you'll hit the 5hr window limits in less than 20 minutes.

With Codex it only happened to me once in my 4.5hr session here: https://simonwillison.net/2025/Dec/15/porting-justhtml/

Claude Code is a whole lot less generous though.

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alostpuppy an hour ago | parent | next [-]

For sure. On one project I kept using codex just to see where the wall was. Took a long time.

	▲	deaux 32 minutes ago \| parent [-]
		It helps that Codex is so much slower than Anthropic models, a 4.5 hours Codex session might as well be a 2 hour Claude Code one. I use both extensively FWIW.

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4 hours ago | parent | prev [-]

[deleted]

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andix 4 hours ago | parent | prev [-]

It really depends. When building a lot of new features it happens quite fast. With some attention to context length I was often able to go for over an hour on the 20$ claude plan.

If you're doing mostly smaller changes, you can go all day with the 20$ Claude plan without hitting the limits. Especially if you need to thoroughly review the AI changes for correctness, instead of relying on automated tests.

	▲	allenu 3 hours ago \| parent [-]
		I find that I use it on isolated changes where Claude doesn’t really need to access a ton of files to figure out what to do and I can easily use it without hitting limits. The only time I hit the 4-5 hour limit is when I’m going nuts on a prototype idea and vibe coding absolutely everything, and usually when I hit the limit, I’m pretty mentally spent anyway so I use it as a sign to go do something else. I suppose everyone has different styles and different codebases, but for me I can pretty easily stay under the limit without that it’s hard to justify $100 or $200 a month.