All Questions
4,320
questions
165
votes
11
answers
398k
views
Why is my transaction not getting confirmed and what can I do about it?
I sent a transaction
without (or with an exceptionally small) transaction fee
using extremely small or unconfirmed inputs
while the stars were not standing right.
For whatever reason, I have been ...
- 1,939
11
votes
4
answers
16k
views
Is it normal to be asked for an advance fee on a withdrawal?
I was approached out of the blue being told that I was supposed to receive a sudden windfall, someone opened an automatic trading account in my name, or offered to invest in a lucrative mining ...
- 77k
206
votes
10
answers
117k
views
What exactly is Mining?
I have heard that mining is for people with ready hardware and blah blah blah... But what exactly is it? Does it operate like real mining? I mean, people talk about it like you are physically mining.
- 2,171
66
votes
3
answers
74k
views
In the ASIC-age, is it worth starting mining Bitcoin at home?
I have recently learned about Bitcoin and would like to get rich quickly into mining.
I have control of a
laptop
library full of ancient computers
powerful gaming PC
cluster of GPUs
an old ASIC, I ...
- 77k
131
votes
7
answers
51k
views
How do you obtain bitcoins?
This is a question many people ask when they're introduced to Bitcoin.
Bitcoin sounds interesting, but if I want to use this system I will need to get some coins, otherwise, there's no way I can ...
- 1,630
116
votes
9
answers
336k
views
How much Bitcoin will I mine right now with hardware X?
Say I have a given piece of hardware (CPU/GPU). Where can I find out how much Bitcoin will I mine per day?
- 26.6k
52
votes
3
answers
14k
views
How does change work in a bitcoin transaction?
It seems that when you send a bitcoin transaction, all the coins in the sending address are spent in that transaction, divided into the amount that you intended to send, and "change", which goes back ...
- 4,769
41
votes
10
answers
10k
views
I am new to Bitcoin, how can I get started?
I am new to both StackExchange and to the new online currency called Bitcoin. I understand what Bitcoin is and how it works, but I was wondering: how do you actually get started with Bitcoin? I have ...
- 515
150
votes
8
answers
56k
views
What can an attacker with 51% of hash power do?
Suppose organization X has 51% of the hash power for a period of 1 week. In this week, what exactly can and can't X do?
- 26.6k
7
votes
1
answer
5k
views
I have lost my wallet, what can I do?
I used to be interested in Bitcoin a few years ago and have recently become aware of it again. I used to have a wallet back then. Given that many years have passed, what I remember is a bit fuzzy. ...
- 77k
87
votes
3
answers
38k
views
How to redeem a basic Tx?
Given a raw, standard Tx (wiki):
01000000
01
26c07ece0bce7cda0ccd14d99e205f118cde27e83dd75da7b141fe487b5528fb
00000000
8b
...
- 43.2k
17
votes
6
answers
33k
views
What would happen if you send Bitcoin (BTC) to a Bitcoin Cash (BCH, aka BCC) address?
Could someone please explain what happens if someone sends bitcoin to a Bitcoin Cash address after the August 1st fork? Would there be a way to recover them?
- 171
79
votes
3
answers
46k
views
How is difficulty calculated?
Can anyone explain me in the plain English how difficulty is calculated. I have a very approximate understanding that it is calculated based on the amount of hash power in all the bitcoin community ...
- 3,370
5
votes
3
answers
2k
views
What kinds of wallets are there?
Can I get short a explanation about cryptocurrency cold/hot wallets?
Are there more kinds?
- 53
29
votes
4
answers
15k
views
Is each Bitcoin address unique?
I am wondering whether each bitcoin address is unique. I would assume yes. Then, how is this enforced given the distributed address generation?
As I understand it, each time an address is generated, a ...
- 393
67
votes
9
answers
93k
views
Where do bitcoins come from and what gives them their value?
Where do bitcoins come from? From the WeUseCoins.com video it appears they are just being produced by "miners" and sold to people. So who backs Bitcoin or gives it its value?
- 14.5k
26
votes
5
answers
38k
views
How do I recover from a cryptocurrency scam?
I lost about $45,000 to crypto investment scam just recently. The
company posed as an investment company that could deliver a certain
percentage in returns if you deposit your Bitcoin with them. At ...
- 339
140
votes
11
answers
81k
views
Is it possible to brute force bitcoin address creation in order to steal money?
Bitcoin users frequently generate new addresses for each transaction they make, which greatly increases the number of bitcoin addresses being used to receive money.
Would it be possible (and ...
- 11.5k
16
votes
4
answers
5k
views
Cannot access my bitcoins because my wallet is still synchronising. What can I do to spend them immediately?
I have purchased bitcoins and have downloaded Bitcoin-QT, but my wallet is taking forever to synchronize to the network.
I can't access my wallet because it is still in the sync process. I have the ...
- 169
10
votes
2
answers
24k
views
Bitcoin Cash accidentally sent to Bitcoin address. Can I get them back?
I managed my Bitcoins Cash in a Electrum Cash wallet on my PC.
From there, I accidentally sent them to another internet based wallet, but didn't notice that this wallet is for Bitcoin and not Bitcoin ...
- 151
113
votes
13
answers
13k
views
Is there a way to set up proof-of-work systems so they would be even more useful?
One of the arguments made against Bitcoin's design choices is that it wastes resources authenticating transactions. In particular, finding small hashes is completely useless for the world.
Are there ...
- 2,016
71
votes
2
answers
96k
views
Can someone explain how the Bitcoin Blockchain works?
I'm trying to figure out how the blockchain works and how to read it via blockchain.info website. Is there a laymen way of explaining how the block chain works and how to read the blockchain to trace ...
- 11.1k
38
votes
2
answers
14k
views
What is the coinbase?
I searched the bitcoin wiki and found references to coinbase, but no clear cut explanation of what exactly it is. I know that miners can tag their coinbases (that is how some sites tell who mined a ...
- 681
51
votes
3
answers
46k
views
How can I run bitcoind in pruning mode?
I read this comment:
You could consider running a pruning node, which is practically the
same as a full node (including security), except it throws away some
of the old history. Version 0.11 ...
- 1,093
194
votes
2
answers
61k
views
How do Bitcoin clients find each other?
What protocols or algorithms are Bitcoin clients using in order to find their peers? I learnt that BitTorrent clients may rely on central computers called trackers. Do Bitcoin clients need any kind of ...
- 2,791
45
votes
2
answers
73k
views
How do I import a private key into Bitcoin-Core?
How do I import a private key into Bitcoin-Qt? bitcoind is nowhere to be found, and pywallet says it requires "bsddb" when I run it, which is also nowhere to be found. I generated some vanity ...
- 2,714
14
votes
2
answers
10k
views
I didn't receive a Bitcoin Payment. What does it mean when the Client is synchronizing?
Bitcoin newbie here. I recently installed the Bitcoin client, and purchased some bitcoins from Mt.Gox. My problem is that my client is constantly synchronizing. I've checked charts and seen that my ...
- 143
44
votes
2
answers
86k
views
How can I export the private key for an address from the satoshi client?
If I want to transfer an address from the satoshi client into a different client, how can I find its private key to do so?
- 14.8k
34
votes
3
answers
47k
views
What is an "unspent output"?
What is the meaning of the term "unspent output" in the Bitcoin protocol?
- 26.6k
66
votes
5
answers
28k
views
What is a soft fork? What is a hard fork? What are their differences?
When people talk about possible changes to how Bitcoin works they sometimes say a particular change can be implemented as a soft fork. What does that mean? How does this compare to a hard fork?
- 8,469
64
votes
3
answers
22k
views
Will there be 21 million bitcoins eventually?
Every x blocks the mining reward is halved. Will the reward be halved forever such that we never quite reach 21 million bitcoins, or will we reach 21 million bitcoins at some point and will the reward ...
- 893
14
votes
9
answers
508k
views
How can I sell bitcoins and transfer the funds to my bank account?
A friend of mine gave me two bitcoins which I now want to sell. I don't understand the process which would enable me send the funds generated to my bank account.
- 141
68
votes
7
answers
162k
views
How many bitcoins will there eventually be?
Since bitcoins are being regularly rewarded to miners, will the number of bitcoins continue to grow indefinitely, or will there be a maximum total number of bitcoins in existence? And if there is ...
- 14.5k
19
votes
6
answers
17k
views
Recipient has “not received” the Bitcoin I sent, but the transaction is confirmed
I sent bitcoins to the address I was given (double checked). The recipient is claiming they did not receive it. I sent them a different payment yesterday at 8:30p and they didn't get it until 4:00am ...
- 191
70
votes
11
answers
11k
views
Will Bitcoin suffer from a mining Tragedy of the Commons when mining fees drop to zero?
One issue that I haven't seen clearly addressed is the possible Tragedy of the Commons in Bitcoin's future (see this answer). 40 years into the future, the only significant direct benefit for honest ...
- 26.6k
56
votes
2
answers
13k
views
What is the longest blockchain fork that has been orphaned to date?
The orphaned blocks view from BlockChain.info shows a recent fork of the blockchain (starting with block 173,928) that went four blocks long before being orphaned.
Other than the controlled rewind ...
- 27.1k
41
votes
5
answers
17k
views
What are the keys used in the blockchain levelDB (ie what are the key:value pairs)?
I am wondering if I can use node.js and levelup to access a copy of the blockchain database directly.
But from what I can see, I need to know the name of the key(s) before I can get any data, as this ...
- 1,354
31
votes
2
answers
26k
views
Redeeming a raw transaction step by step example required
I am looking, specifically, for a step by step example transaction of sending Bitcoin which uses an actual transaction (How To Redeem A Basic Txn, from a few years back, does a great job of outlining ...
- 5,308
60
votes
4
answers
33k
views
What keeps the average block time at 10 minutes?
I've been told "the network" sets the difficulty level such that there will be one new block mined every ten minutes.
I imagine the rich would instead prefer to keep difficulty as high as possible to ...
- 2,030
37
votes
3
answers
54k
views
How can I start mining Bitcoin?
Ok. I don't care if I make only a small amount of bitcoins mining. I want to mine.
How do I setup my machine (amd x64 4.6Ghz 6GB/RAM with GeForce Nvidia 7300, LinuxMint 10) to start mining?
Is it ...
- 983
66
votes
6
answers
37k
views
What is meant by Bitcoin dust?
I've seen the term "dust" used to describe small transactions that might be considered as spam by the Bitcoin network. Is there is a generally accepted definition of this term?
- 3,332
19
votes
3
answers
21k
views
Are there Bitcoin password crackers I can use to recover forgotten passwords?
I've lost the password to one of my wallets (it's a small one, don't worry). I was sure I remembered the password ... but evidently I don't.
Is there a program that I can use to brute-force my ...
- 26.6k
163
votes
6
answers
293k
views
What are bitcoin miners really solving?
As with mining, what are the bitcoin miners really solving? I read they are solving hashes, but what does that really mean. Can we see what they are solving? Can someone give an example of what a ...
- 11.1k
66
votes
9
answers
36k
views
How anonymous are Bitcoin transactions?
I read some sources that say Bitcoin transactions are anonymous, some that say they are semi-anonymous, and some that say they are not anonymous at all. In what ways are the transactions anonymous ...
- 3,374
23
votes
4
answers
34k
views
How can I setup Bitcoin to be anonymous with Tor?
Bitcoin is billed as many things, among them its anonymity is highly regarded. While it is true that a transaction does not identify a user or wallet, recent news shows that there is the potential for ...
- 3,289
16
votes
2
answers
2k
views
How can we be sure that a new block will be found?
How do we know the HASH function will produce an output that fulfills the difficulty, i.e. is below 0000...xxxx...xxx?
Is it possible that no proof will be found so that the HASH will produce that ...
- 261
19
votes
2
answers
6k
views
UTXO model vs. account/balance model
I understand that Bitcoin uses unspent tx output and Ethereum account balance based. However, recently there are lots of discussions on that Bitcoin's UTXO database has become too big. Does this mean ...
- 657
60
votes
3
answers
48k
views
What are bitcoin "confirmations"?
When I receive bitcoins I see a certain number of "confirmations" in the client. What do these mean? Why do most sites make me wait for 6 "confirmations" before a purchase will go through?
- 5,432
42
votes
4
answers
77k
views
Where is the data folder for Bitcoin-Qt?
Where can I find the blockchain, wallet.dat, etc. on each of the operating systems Bitcoin-Qt supports?
- 14.8k
40
votes
3
answers
49k
views
Who gets Bitcoin transaction fees?
Whenever I send bitcoins from one wallet or one exchange to the next there is always a fee. This makes sense with the exchange sites, they are just collecting the fee so they can make a living. What ...
- 731