# Gas costs

Since XPress is a fully on-chain order book exchange, each order placement is associated with a gas fee.

The table below contains the median gas costs of most common operations on XPress on-chain order book, and corresponding dollar equivalent on Sonic.

| Operation           | Gas Units | Gas Cost in $ on Sonic |
| ------------------- | --------- | ---------------------- |
| Market Order (Swap) | 100,000   | \~$0.0001              |
| Place Limit Order   | 200,000   | \~$0.0001              |


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