> For the complete documentation index, see [llms.txt](https://docs.kyte.sh/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.kyte.sh/guides/buy.md).

# Buy an option

Pay a premium, receive an Option NFT you can exercise until expiry.

Page: [kyte.sh/market](https://kyte.sh/market)

{% stepper %}
{% step %}

### Pick a token

The chart shows its price in ETH from Uniswap v4 swaps (or a Robinhood quote feed for stock tokens), with every open strike drawn as a horizontal line and past fills and exercises as markers. Choose 1m, 5m, 15m or 1h candles.
{% endstep %}

{% step %}

### Browse open offers

Each row shows kind (call or put), amount, strike per token, premium, expiry, distance from spot ("vs spot") and break-even.
{% endstep %}

{% step %}

### Review

Click **Buy** and review the dialog: premium, fee and what you receive.
{% endstep %}

{% step %}

### Confirm in your wallet

The site sends one transaction. You pay the premium in ETH, and `maxPremium` protects you if anything about the offer changed.

{% tabs %}
{% tab title="Call" %}

```solidity
Router.buyWithETH(id, maxPremium)
```

{% endtab %}

{% tab title="Put" %}

```solidity
Router.buyPutWithETH(id, maxPremium)
```

{% endtab %}
{% endtabs %}
{% endstep %}

{% step %}

### Hold your option

The Option NFT lands in your wallet, and the position appears under **Positions → Holding**.
{% endstep %}
{% endstepper %}

## When an option pays off

<figure><img src="https://996751035-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FVsnNtaBRxeClOSpEHWrf%2Fuploads%2Fgit-blob-0b06176b3e078062e98f89beb5d81c967f5fffbb%2Fdiagram-payoff.png?alt=media" alt="Profit and loss of a covered call and a cash-secured put when exercised, for the holder and the seller"><figcaption><p>What each side makes or loses when the option is exercised</p></figcaption></figure>

The premium is the most a buyer can lose. A call pays off when the token trades above the break-even, a put when it trades below. Exercise before expiry: the transaction must land while `now < expiry`.

**What happens to your premium:** 3% goes to the FeeVault and 97% goes to the seller, in WETH.

{% hint style="warning" %}
You cannot buy your own offer (`SelfTrade`), and you cannot fill an offer after its fill deadline (`OfferExpired`).
{% endhint %}


---

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