What running an AI coding agent 24/7 actually costs

Short answer: there are two costs, and people only plan for one. The machine that stays awake is a few dollars a month and it is predictable. The AI is the part that can surprise you, and which pricing model you are on matters more than how many hours you run.

The machine

A small server that never sleeps costs a few dollars a month. It costs the same whether it works all night or sits idle, because you are renting the machine, not the hours. This half of the bill is boring, which is exactly what you want from it.

Size matters for speed, not for whether it works. More processing power means builds finish faster and you can have more than one thing being worked on at the same time. It does not change what is possible.

The AI, which is where people get caught

This is the half that varies, and it comes down to which way you are paying.

Paying per use. You are charged for how much the AI reads and writes. An agent working unattended overnight reads a lot, because it keeps checking its own work. Left running with no limit, this is where a bill you did not expect comes from.

Paying a flat subscription. You pay one price and your usage sits inside your plan's limits. An overnight run uses your allowance rather than adding to a bill. If you hit the limit, it waits instead of charging you more.

This is why KAppMaker AI asks you to bring your own Claude account rather than reselling AI usage. Your AI cost follows your own plan, and we never add a markup on top of it. Our bill is only for the machine.

Does running it all night cost more than running it for an hour?

For the machine, no. Same monthly price either way.

For the AI, it depends entirely on the model above. On a flat subscription, an overnight run is simply using something you already paid for, during hours you were asleep anyway. On per use pricing, more hours means more cost, so you want limits.

A realistic monthly picture

• Doing it yourself: a few dollars for the server, plus whatever your AI plan costs, plus your own time when something breaks.
• With us: from $14.99 a month with the machine included and looked after, plus your own Claude plan, and nothing added on top.

The one thing worth checking first

Before you leave anything running overnight, find out whether you are on per use pricing or a flat plan. That single answer decides whether unattended work is basically free or something you need to watch. Everything else about the cost is small and predictable.