What is a Limit FOK order?
FOK stands for ‘Fill or Kill’, this is a limit order with the condition that the entire order must be filled 100% or the order gets cancelled.

For example: You want to buy 1 entire BTC at 9000 USD but there is only half a BTC for sale at that price, executing the order at that price would end up with the order being completely cancelled.

Partial fills are not accepted with this order type unlike the Limit IOC order type.

When is a Limit FOK order typically used?
A ‘fill or kill’ order is commonly used if you want a specific amount of an asset at a set price or none at all.

Let’s say you wanted to buy 2 BTC at 4000usd, but if you couldn’t get exactly 2 BTC at that price you don’t want any at all.

This can be useful in certain scenarios but you should always weigh the pros and cons of this order type as there could be missed trading opportunities if the market is moving fast.