BTCex.com Limits to 2 DIGITS Trade Precision !!! BEWARE.

[BkkCoins]

I was just poking around trying this exchange for converting some NMC > BTC.

Turns out their interface truncates all amounts to 2 decimal places. So when you send NMC to them you lose anything after the 2 decimal. When you sell for BTC  - again lose after the 2nd decimal.

My 8.32101261 -> 8.32 ( lost 0.00101261 )
Sell 8.32 @ 0.0044  -> 0.03 ( lost 0.006535 )
Balance after this 0.03 BTC.
Cost to withdrawl BTC, 0.01 BTC.

Amount rec'd for 8.32101261 NMC -> 0.02 BTC.

Resulting conversion: 416 NMC/BTC, or roughly 50% lost compared to market.

BEWARE of this scam site. I didn't realize this before depositing NMC to the address they provide. But YOU NOW ARE AWARE!

I can't believe BitcoinCharts even lists this site on their exchange listing.

Edit: Got my BTC out of there before anything else scammy happens. Net Result: Sent 25 NMC in and got 0.09 BTC out. The rest vanished in truncations and fees. If you treat the truncation as fee then this is the same as selling 25 NMC for 0.09 BTC = 277. Given the actual trade happened at 227 NMC/BTC this is in essence hidden fees of 22%. SO BEWARE!

[BkkCoins]

Reply from BTCex.com when I complained about how they calculate trades:

Code:

> The trade engine may calculate beyond 2 digits but anything beyond 2
> > digits is not credited to account balances.
> > 
This is wrong. This values just not shown, otherwise would have to
display amounts such as 1.2345678901234445675675689123456789123456789.
But values like that are saved on users accounts.

> > My trade shows up in the history page as,
> > 
> > 8.32 * 0.0044 BTC/NMC = 0.036608 BTC.
> > And then it show my balance credited with 0.03 BTC.
> > 
And on your account really placed 0.036534784 BTC (0.036608 minus fee
for trade)

> > I did another trade 16.86 * 0.0044 = 0.073392 BTC.
> > And then it credits my balance with 0.07 BTC.
No, 0.073245216 really
And after this operation your balance was 0.10978 BTC

> > When I try to send the BTC out to my address it does not allow more
> > than 2 decimal places. 
Yes

> > It actually prints and error message saying "too much detail".
> > 
According to our rules users can withdraw bitcoin amounts with 0.01
precision. This is to ensure that the withdraw will not cause of any
additional fees of bitcoin network.

> > I've seen Tradehill get thrashed on the forum for not calculating with
> > the full 8 digit values. 
> > Dropping 6 digits of accuracy for trades is nothing short of robbery.
> > 
Believe me: you do not want to see any site filled with the numbers like
this:

1.002345678901234445675675689123456789123456789
1.6756756891234567891234567892345678901234445
1.23456789012344456756756891200000003456789123456789

etc.

> > Consider my two trades today totalling 25 NMC.
> > (8.32 * 0.0044) + (16.86 * 0.0044) = 0.036608 + 0.074184 = 0.110792
> > BTC
> > I should have received this minus 0.2% * 2 fee in my BTC balance.
> > 0.110792 - .4% = 0.11034883 BTC.
> > I actually received ONLY 0.10 (since it was 0.03 and 0.07, both times
> > truncated).
> > So on my trades my ACTUAL FEE paid was (0.10 - 0.110792) / 0.110792 =
> > 9.7%
> > Round that off to a 10% FEE which is about 9.8% more than documented!
> > 
> > That's a 9.7% Commission you charged me due to hidden truncations.
> > 
> > Your site fee schedule should make this clear - otherwise it's simply
> > a scam.

If what he said was true I would have 0.11 in my account balance not the actual 0.10 balance resulting from truncation.

Has anyone here ever seen any other exchange or pool decide that truncating to 2 digits on transfers out will "save fees on the network" and be a user benefit?

[DeathAndTaxes]

I have never used this exchange (yet) but I really don't understand your issue.

As he explained, you had 0.109xxx btc's in your account.

And, as he explained, they allow withdrawals that are multiples of 0.01. So, of course, the maximum you can withdraw is 0.10. What's the problem?

Such things are standard across all brokers.

If you care so much about the remaining 0.009 btc that are surely *still* credited to you in your account, close your account. When that happens, the brokers typically refund anything that's remaining.

Heck, in fact, many brokers will simply "eat" anything under $10 (credit OR deficit) when an account is closed - and I have seen both.

I don't really see the reason to make an issue out of it. Again, their explanation and detailed calculations seemed pretty reasonable to me. If I misunderstood, please correct me.

Guess you missed the part where they round trades to the nearest 0.01 also.  It is pretty scammy.  Serves no purpose other than to grab a hidden fee from every transaction.

I mean it isn't physical coins they are moving around.  Any computer can handle 8 digits just as easy as 2.

[BkkCoins]

Such things are standard across all brokers.

I don't know of any other exchange that does this. If they did truncate values then I wouldn't be using them anyway and I'm pretty sure other traders wouldn't either. I recall the huge outcry back when Tradehill started and people heard they use "float" datatypes to calculate trades.

I'm pretty sure that the remaining 0.009 BTC is not in my account. There is no indication of it.
I'd be happy to close it and have it sent out though if that were even an option.

But the main point is that none of this is disclosed up front and when I decided to send my NMC there to trade I saw no indication I'd end up paying 20% fees for the transaction. The first I saw of this was that my NMC balance was truncated and by then it was too late to do anything at all.

At the very, very least if the extra BTC portions are actually still on account then that needs to be displayed as otherwise there is no way to enter orders and do trades that make use of the balance remaining, and it may just as well be lost. The whole thing seems ludicrous and poorly conceived.

Maybe it's just inept design, or maybe it was purposefully done to grab fractional trade fees. I'm just alerting users so they know before they send funds into this leaky account.

Furthermore BTC are always calculated with 8 digits precision. Some day when 1 BTC = 100USD this truncation will be costing dollars per trade. Maybe you're used to USD where the normal precision is 2 digits.

[BkkCoins]

He did say that. And it may be that the account balance is there if he says.
But how do you trade with what is actually in your account if you can't see the full balance?

eg. I may have 8.32123234 BTC on balance

But it only shows me 8.32 so I can't buy or sell the remaining part. It is forever stuck in their system unless I get out my calculator and scan thru the history page manually adding up transactions to get my actual balance. And I'm not sure if you can enter a trade "with too much detail" as when I tried before it gave me that error message.

This is why I figured it may be inept design rather than intended cheating. In his most recent email he says,

Code:

I repeat: we calculating all operations to within at least 16383 decimal
digits after dot. 

Whatever that really means, it's a bit pointless if you cannot know the balance.

[StewartJ]

OP is doing a huge disservice with the title of this post.

While I have not traded on this exchange I have observed the bustle of trade activity in Litecoins.

Never heard of anyone complaining in the chat room there.

[BkkCoins]

Ok. I changed the title to be more accurate. I still think this is a pretty egregious design decision and either the site owner is being naive or just hiding his motives. After his responses I'm guessing the former. Essentially he collects bit-dust off all his account holders since they can never use it or get it back. But also it affects trades because you can never trade your actual value on account.

And for what? So you have the simplicity of not seeing "more confusing numbers" is what he seems to explain it with to me.

Trading is not an approximate / rough guess type of business. I've never seen a stock market broker or bank that just rounds the pennies off because it isn't worth the hassle of viewing them.

And obviously he is confused about his 16383 digits precision. Unless he's using a special arbitrary precision math library (why?) he's somehow confused between binary bits precision (14 bits = 16384 possible values) and decimal digits of precision. I don't imagine he actually stores 16383 digits in the database for each value, and float/double certainly doesn't offer anything near that many digits. Nor does it make sense to want that many digits. This is why I now believe it's just poor site design rather than outright malicious intent.