> For the complete documentation index, see [llms.txt](https://size.club/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://size.club/docs/how-size-works/what-is-a-key.md).

# What is a Key?

A Key is your entry ticket to a Trial. One Key, one attempt. Size consumes the Key when the Trial starts.

The Key is also your whole downside: whatever happens inside the Trial, the most that run can cost you is the Key. You are trading a simulated balance against live prices, never your own money. See [What you risk and what you can win](/docs/how-size-works/what-you-risk-and-what-you-can-win.md).

## Where Keys come from

* Free Alpha Key on signup
* Store purchase ($1 Alpha Key)
* Occasional rewards or drops when Size runs them

## Key states

| State    | Meaning                      |
| -------- | ---------------------------- |
| Unused   | Ready to spend on a Trial    |
| In use   | Trial started. Key is locked |
| Consumed | Trial finished. Key is gone  |

See [Inventory](/docs/wallet-and-store/inventory.md).

## Alpha Key

|                |                 |
| -------------- | --------------- |
| Free on signup | 1 Alpha Key     |
| Store price    | $1              |
| Win prize      | $100 Alpha Life |

Future Key tiers: [Product tiers](/docs/how-size-works/product-tiers-keys-and-lives.md).

## Related

* [Size Trials](/docs/playing-a-trial/size-trials.md)
* [The Store](/docs/wallet-and-store/the-store.md)
* [Practice Trials](/docs/playing-a-trial/practice-trials.md)


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