Bitcoin Forum

Suppose that the lowest bid is $14 and I issue an order to sell 1BTC at $10. Do I get $10 or $14? (and the same thing for buying)

Your order is matched to the best available bid (if you are selling) or ask (if you are buying). So in that case you would get $14.

The usual reason someone puts an order in like this is to buy (or sell) a large quantity. For instance, if you put in a sell order for 10,000 BTC at $10, it would fill every bid order until the bids went below $10 or you ran out of coins.

Thank you for the answer. In my case, I just wanted to sell some bitcoins at MtGox, but by the time I filled in all the details, the price shifted a little and my order was pending...

So if I just want to sell, I can put something like $1 and I will get the best price currently on the market, right?

That's correct.

This is actually a matter of exchange policy.  Almost all exchanges go with the price on the older of the two orders in the match, but you need to check with the exchange to be sure if the exact behavior matters to you.

You should never tell an exchange that you are willing to accept a price that you aren't actually willing to accept.

OK, thanks for the advice. I think that all this trouble could be avoided if there was an "Instant Sell" option that would sell at the best price...

Instant Sell assumes that it would sell by the price which buyers are willing to pay. And it may not be good for you.

No, almost all excahgnesa re obliged to give you the BEST price, MOST then match the oldest order at that price.

Talking SERIOUS exchagnes here - NYSE, NASDAQ, CBOT, CME, NYMEX, GLOBEX.

It is ALWAYS matching best price.

Suppose that I want to buy $100 of BTC to spend on Silk Road. I couldn't care less if I am buying at $13.34 or $13.41 because I don't plan to sell them 5 minutes later to earn $0.5. I just want to buy stuff with bitcoins. For someone who wants to buy stuff with bitcoins, these exchanges make you do lots of useless calculations...

Well...it really depends on what exchange you use and how they process orders...you didn't say which exchange.

My exchange engine I'm building won't allow you to place a sell order lower than the current buy order or vice versa.  Instead, my engine directs you to perform an instant trade instead of a market order.

Don't take this the wrong way, but this is the way you'd design an exchange if you see gambling or amusement as the primary purpose.  If you see those as a sideshow around the primary purpose of buying and selling BTC, you'll do everything as limit orders.