Bitcoin Forum

Other => Beginners & Help => Topic started by: ehmdjii on July 18, 2012, 05:58:36 PM



Title: Transaction fees higher than yesterday?
Post by: ehmdjii on July 18, 2012, 05:58:36 PM
yesterday i wanted to make a small transaction of 0.15 BTC. the official client wanted to have 0.0025 BTC fee.
i declined this.

today i just wanted to make the same transaction but now the client wants 0.003 BTC fee.
how is this possible?

there have been no other transactions to my wallet since yesterday.


Title: Re: Transaction fees higher than yesterday?
Post by: MoonShadow on July 18, 2012, 06:00:07 PM
yesterday i wanted to make a small transaction of 0.15 BTC. the official client wanted to have 0.0025 BTC fee.
i declined this.

today i just wanted to make the same transaction but now the client wants 0.003 BTC fee.
how is this possible?

there have been no other transactions to my wallet since yesterday.

Are you sure?  I can't recall mine ever asking for less than .005 BTC.


Title: Re: Transaction fees higher than yesterday?
Post by: ehmdjii on July 18, 2012, 06:04:14 PM
yeah, i am pretty sure!
http://www.deviantsart.com/10tphon.jpg


Title: Re: Transaction fees higher than yesterday?
Post by: notme on July 18, 2012, 06:09:06 PM
Which client and what version?


Title: Re: Transaction fees higher than yesterday?
Post by: ehmdjii on July 18, 2012, 06:10:17 PM
official client 0.6.3


Title: Re: Transaction fees higher than yesterday?
Post by: Foxpup on July 18, 2012, 08:09:29 PM
Transaction fees vary depending on several non-obvious and seemingly arbitrary factors. If you have recently received a large number of small payments (eg, from a faucet), these coins are considered "low priority" (to discourage people from spamming the network with such transactions) and spending them requires a higher fee than normal. Also, transactions requiring several "input" coins take up more data, again requiring a higher fee. It's semi-random which coins the client uses when making a transaction, so the fees will appear random as well, but there is a method to its madness. :)


Title: Re: Transaction fees higher than yesterday?
Post by: DeathAndTaxes on July 18, 2012, 08:22:38 PM
Foxpup has it.  There is no single fee.  The mandatory fees are calculated by the client based on the transaction inputs.  The number of inputs (and thus tx size not to be confused with value) and the age of the coins determine the mandatory fee.

The reason you are getting hit with higher fees is your transactions are seen by the network as the most dangerous.  They are very large (in terms of bytes) and very low value (in terms of BTC).

A rule of thumb is One Bitcoin Day to avoid mandatory fees.  If you receive 1 BTC and wait 1 day it will be old enough to avoid being charged the mandatory fee (of course you can still add an optional fee to increase processing).  If you are spending 10 BTC input the time would be 1/10th of a day (~2.4 hours).  If you are spending a 0.1 BTC input you need to wait 10 days for the input to be old enough to avoid fees.

Note:  The the One Bitcoin Day is only an approximation.  In reality priority is calculated based on blocks so if you want to use the real formula it is:

Code:
priority = sum(input_value_in_base_units * input_age)/size_in_bytes

value is in satoshis (0.00000001 BTC)
age is in blocks
priority must be >= 57,600,000 to be considered high priority.

low priority transactions must pay a mandatory fee (spam prevention & DDOS protection)
mandatory fee is 0.0005 per KB (round up).

Transactions are exempt from fee calculation both of the following are true
a) the tx is less than 10KB
b) ALL (including change) outputs are >= 0.01 BTC

Or you can approximate as One Bitcoin Day.


Title: Re: Transaction fees higher than yesterday?
Post by: FreeMoney on July 18, 2012, 08:58:33 PM
yesterday i wanted to make a small transaction of 0.15 BTC. the official client wanted to have 0.0025 BTC fee.
i declined this.

today i just wanted to make the same transaction but now the client wants 0.003 BTC fee.
how is this possible?

there have been no other transactions to my wallet since yesterday.

Are you sure?  I can't recall mine ever asking for less than .005 BTC.

Don't you mean .0005?


Title: Re: Transaction fees higher than yesterday?
Post by: MoonShadow on July 18, 2012, 08:59:07 PM
yesterday i wanted to make a small transaction of 0.15 BTC. the official client wanted to have 0.0025 BTC fee.
i declined this.

today i just wanted to make the same transaction but now the client wants 0.003 BTC fee.
how is this possible?

there have been no other transactions to my wallet since yesterday.

Are you sure?  I can't recall mine ever asking for less than .005 BTC.

Don't you mean .0005?

Maybe so...


Title: Re: Transaction fees higher than yesterday?
Post by: FreeMoney on July 18, 2012, 09:02:03 PM
yesterday i wanted to make a small transaction of 0.15 BTC. the official client wanted to have 0.0025 BTC fee.
i declined this.

today i just wanted to make the same transaction but now the client wants 0.003 BTC fee.
how is this possible?

there have been no other transactions tomy wallet since yesterday.

Ah ha, there must have been transactions -from- your wallet since last attempt correct?

You must have a wallet with a ton of small tx. When you made another tx it used up some of the (probably slightly) larger inputs and so now you need even more of those tiniest inputs to make up .15.

You are using up a relatively large amount of system resources for tiny amounts so you either need to pay for it or wait a while.


Title: Re: Transaction fees higher than yesterday?
Post by: DeathAndTaxes on July 18, 2012, 09:27:48 PM
https://en.bitcoin.it/wiki/Transaction_fees

Note the mandatory fees aren't intended as revenue producing mechanisms.  Supply and demand, with users paying miners for priority processing will be the basis for a fee economy.   The purpose of mandatory fees exist to protect the network.  If your transactions "look spammy" you will get hit with a fee. If your tx never look spammy you will never pay a fee.  The mandatory fees ensure that if someone tried to destroy Bitcoin by spamming it they would quickly rack up some massive tx costs and have little to show for it.