With only 3 users, can they cover my cloud bill?

Buddy, you've hit the nail on the head with this question. It's something every product person has grappled with.

The answer is simple: it entirely depends on how much you charge them and how 'heavy' your service is.

You can't just look at the number '3 users'; you need to do the math. Let's think of this as opening a physical store.

Your 'cloud bill' is like your store's 'rent and utility bills'. Your '3 users' are your first three customers.

Now the question becomes: Can what these 3 customers spend cover the store's rent and utilities?

See, it becomes much clearer when you think about it this way, right? There are two key points here:

1. How expensive are your 'rent and utilities' (cloud service costs)?

This varies greatly depending on your choices, and the difference can be huge.

If you're building a 'lightweight' application: like a simple blog, an informational website, or a utility mini-program. Users just come to read text or check data. In this case, your server might only need the minimum configuration, costing just a few dollars a month, or many cloud providers even offer free tiers, so you won't spend a dime. In such a scenario, let alone 3 users, even 300 users might still be within the free tier.
If you're building a 'heavy' application: like a video streaming site, an AI application requiring extensive computation, or an online game. Such services are very 'resource-hungry'.
- Compute-intensive: For example, AI image generation. Every time a user clicks, the server has to work frantically. It's like a restaurant cooking with the highest flame – the gas bill (compute cost) skyrockets.
- Bandwidth-intensive: For example, when users watch videos stored on your server, data is transferred from your server to their phones. This process incurs a 'toll fee' (bandwidth cost). The more users watch, the more expensive the toll.
- Storage-intensive: For example, if you build a cloud drive and users store a large number of files, you'll need to rent a large warehouse (hard drive space), which also costs money.

For 'heavy' applications, costs can start from hundreds to thousands of dollars a month.

2. How much do your 'customers' (users) pay?

This is the other big question.

If your service is free, then let alone 3 users, even 30,000 users won't cover your bill. You'll have to rely on advertising or other means to make money.
If each of them pays you 10 dollars a month, your total monthly income is 30 dollars. This amount is only enough for a lightweight application to get by.
If they are enterprise clients, and each pays you 10,000 dollars a month, then your monthly income is 30,000 dollars. This amount is enough for you to hire a small team and rent a decent server.

My advice to you:

In the early stages, frugality is paramount: All cloud providers (Alibaba Cloud, Tencent Cloud, AWS, etc.) offer 'free tiers' or 'new user discounts'. Make full use of them! Choose the most basic and cheapest configuration. Your goal, before validating product viability, is to drive costs down to near zero.
Don't expect users to sustain you yet: The value of your earliest users isn't in the small amount of money they pay, but in their feedback. They are your 'guinea pigs,' helping you find bugs and telling you what works well and what doesn't. Their existence helps you refine your product to attract the next 300, 3000 users.
Calculate the 'cost per user': Simply estimate how much cloud resource cost you'll incur to maintain one active user. This way, you'll have a clear idea, and when you price your product in the future, you'll at least not lose money.

To summarize:

In the early stages of a startup, don't think about '3 users covering the cloud bill'. Instead, you should be thinking: 'How can I serve these 3 seed users with the lowest possible cost (even zero cost), and gain valuable feedback from them to validate that my idea is correct?'

First, make a good product and prove that people are willing to use it, and even pay for it. Once the user base grows, costs and revenue will naturally enter a virtuous cycle. Getting hung up on a few dollars of cloud bills at the very beginning can lead you astray.