> ## Documentation Index
> Fetch the complete documentation index at: https://docs.linkio.world/llms.txt
> Use this file to discover all available pages before exploring further.

# Developer Fees

## Overview

LINK lets you add a custom markup on top of the base exchange rate for your users. The markup is a percentage deducted from the customer's payout — it never inflates the headline rate shown to LINK.

Markups are configured from your **LINK Dashboard** under **Settings → API Markups**.

***

### Markup Types

There are two independent markup fields, each covering a different product:

| Type              | Applies To                               | Max |
| ----------------- | ---------------------------------------- | --- |
| **Retail Markup** | Retail on-ramp and off-ramp transactions | 2%  |
| **B2B Markup**    | OTC / Business API transactions          | 2%  |

Both fields default to `0`. You can set them independently — enabling a B2B markup does not affect retail transactions and vice versa.

***

### How It Works

When a markup is set, LINK applies it on top of its own exchange rate before the customer sees the final payout:

1. LINK computes the base rate for the transaction.
2. Your markup percentage is applied on top — reducing the customer's payout by that proportion.
3. The final rate and payout are returned to your system and shown to the customer.

The fee is tracked at the transaction level (`linkFee` for LINK's share, `customerFee` for your markup share).

***

### Configuring Your Markup

1. Log in to your **LINK Dashboard**.
2. Navigate to **Settings → API Markups**.
3. Enter a Retail and/or B2B markup value between `0` and `2` (percent).
4. Click **Save Changes**.

Changes take effect on the next transaction — no redeployment or API key rotation required.

***

[Currency Limits](/docs/currency-limits)

[FAQ](/docs/faq)