Order types

Most traders only need GTC limit orders. The other types exist for specific situations.

Time-in-force

A limit order's time-in-force controls how long it stays on the book.

Use IOC if you want to take the current best price without leaving a resting order behind. Use FOK if a partial fill would be worse than no fill.

Post-only

Tick Post-only to guarantee your order is a maker order. If the order would immediately match an existing resting order — and so be a taker — it's rejected instead of filled.

This is the right choice when:

• You want to earn the maker rate (fee-free under the current schedule).
• You're providing liquidity at a specific price and don't want to sweep the book if it just moved.

Cancel-replace and amend

To change a resting order's price or quantity, you have two options:

• Amend — modifies the resting order in place. Loses queue priority in some cases but is otherwise atomic.
• Cancel-replace — atomically cancels the old order and places a new one. If the cancel fails (e.g., the old order already filled), the new order is not placed.

Both are available from the Open Orders list. Use the one that matches your intent.

Self-trade prevention

If you somehow have a buy order and a sell order in the same market that could match each other, self-trade prevention kicks in. By default, neither side fires — both orders stay open. See Self-trade prevention for the API options.

Batch operations (API only)

If you trade through the API, you can place up to 15 orders in one request and cancel up to 200 orders in one request. Useful for market-makers updating quotes across many price levels.

The web UI doesn't expose batch operations directly. See the API reference if you need them.