26

I am not a lawyer, but... The Coinage Act of 1965, Section 31 U.S.C. 5103, entitled "Legal tender," states: "United States coins and currency... are legal tender for all debts, public charges, taxes, and dues." In the USA all monetary debts can be paid in US dollars. Second, while bitcoin is legally a payment method in the US, it does not have legal ...


22

There are a variety of variables that affect Bitcoin pricing on the exchanges. Some are: Market size Exchange volume Price of entry Market size: Relatively speaking, the market for Bitcoins is small. In April of 2013 it was about 1.2 billion USD, and a few days later dropped to below 750 million USD. That's a small market cap, which means, among other ...


19

I made a payment to a company for a product more than a year ago in bitcoin. The amount that I paid then was equivalent to $75. Now the company has failed to provide the product and they and I both agree that I'm owed a refund. However, we disagree on the means. The company wants to refund me - in bitcoin if I wish it - to the value of $75 of ...


16

http://api.bitcoincharts.com/v1/csv/ Each of these files have every trade executed on the given exchange (except the last 15 minutes or so).


15

I am developing the ccxt cryptocurrency trading library, check it out on GitHub: https://github.com/kroitor/ccxt It is a library for cryptocurrency trading and e-commerce with support for many bitcoin/ether/altcoin exchange markets and merchant APIs. With it you can access market data and trade bitcoin, ether and altcoins with more than 70 (!!!) ...


15

To my knowledge, bitcoin is not traded on any stock markets. It is traded directly on exchanges specialized in cryptocurrencies. These exchanges don't necessarily close, and therefore trades are always occurring. Your wallet is reading the price feed from one of these exchanges (you can probably configure which one if you look at the settings), and is ...


14

A refund should be issued using the same payment method that was used at the time of purchase. This also serves an anti-fraud measure for the cases where a purchase was made on a stolen medium (eg a credit card) but the scammers request a refund in a different medium (eg cash) as soon as the payment goes through because all they want to do is take the money ...


13

You have people that have BTC or currency already in their accounts. Those people can claim: "I will buy/sell X amount of Bitcoins for Y amount of currency". If you divide one by the other, you have the exchange rate for that particular transaction. If a buy and sell transaction overlap, they are executed and removed from the system. After all such ...


13

One thing a lot of people fail to notice is the decreasing volume at the exchanges. If we look at the USD volume - and not at the bitcoin volume, which is misleading because bitcoins are now worth much less - we can see a spike in June and a decrease afterwards: The news reports in June attracted lots of people who were curious about bitcoin. A part of ...


13

Namecoins are used to register .bit domains: http://dot-bit.org/HowToRegisterAndConfigureBitDomains They're also bought and sold by speculators, but DNS registration is their original purpose.


13

All historical data from any exchange available at Bitcoin Charts: Markets API Historic Trade Data Trade data is available as CSV, delayed by approx. 15 minutes. It will return the 2000 most recent trades. Format: https://api.bitcoincharts.com/v1/trades.csv?symbol=SYMBOL[&start=UNIXTIME] Returns CSV with columns: unixtime,price,amount ...


13

Bitcoin is not a stock. It's a decentralized currency and its markets are open 24/7.


12

Some possible reasons I read: Merchant adoption through payment processors While merchant adoption is growing, it is currently mostly through payment processors, hardly any merchants keep a significant portion of their bitcoin earnings. With the broader selection of things to spend bitcoins on, more people are shopping with bitcoins, yet, not necessarily ...


11

People are not holding their bitcoins as long. I've speculated elsewhere that this might have something to do with the hedging mechanism implemented by Silk Road. We all want people to use bitcoins for transactions; unfortunately they only have value in proportion to the length of time for which people hold them. If everybody bought bitcoins (using fiat) ...


10

You could use the JSON encoded ticker data available from MtGox at: https://mtgox.com/api/0/data/ticker.php Just use whatever your language's equivalent to cURL or wGet is and parse as appropriate.


10

Given that bitcoin has increased in value, one of us has to profit from this. If you hold the bitcoins while the value goes up, you are the one entitled to profit from it, because you also risk holding while the value drops, and then you're the one stuck with the loss. Imagine the 10,000 BTC pizza transaction were refunded now: would the purchaser be ...


9

It is because it is more expensive and has delays longer and more unpredictable to get $USD out of MtGox, and because they are facing regulatory and lawsuit problems. US branch of MtGox, known as Mutuum Sigillum, may bankrupt or get more assets seized. Simply put, a dollar at MtGox is not worth as much as a dollar elsewhere. MtGox is more accessible/less ...


9

When exchange 'A' sells bitcoins for 200 dollars and exchange 'B' buys bitcoins for 300 dollars, there will be people who buy at 'A' and sell at 'B' as long as they can make money on it. This is called 'arbitrage'. Because of the open markets, people are free to do as they please, so there are people who buy and sell solely to make mere cents on the dollar. ...


9

You can't include the USD amount, but you certainly can include the btc amount in the QR code. The QR code essentially embeds a text like this: bitcoin:1ArmoryXcfq7TnCSuZa9fQjRYwJ4bkRKfv?amount=0.005 Note the amount here is the amount in BTC. You can generate a QR code for that text using gobitcoin.io. If you just want to insert an image, you can use ...


8

http://bitcoincharts.com/charts/mtgoxUSD has historical charts. These 3 all have 'live' charts: http://btccharts.com/ http://mtgoxlive.com/ http://bitcoin.clarkmoody.com/


8

Technology is helping with this. For instance, I don't know what the fair price is for a GPS device that I see for sale at Best Buy, for instance. I whip out my mobile and do Amazon price check to see what the price is elsewhere. This app could just as easily display the price in BTCs. So therefore, we already are getting in the habit of distancing from ...


8

All you'll ever get is speculation. Nobody knows why prices change. It's just like when you listen to the news and they tell you that stocks dropped because of "profit taking". Clearly, people were selling if stock prices dropped. But nobody really knows if people were taking profits, cutting losses, or something else entirely. These are emergent behaviors ...


8

As with any traded commodity the price largely depends on the confidence of the buyers and sellers in the future evolution of the price. Basically you pay whatever you feel it is worth. Like stocks this changes over time, as the company or the bitcoin economy in our case evolves. The wild price swings are not that really that surprising then when it is ...


8

The Bitcoin price is the result of a free market. There is no central authority that could by order "pump money into the system". This currently happens anyway - but decentralized. When more people buy Bitcoins the market cap increases. With a higher market cap a single trade has a lesser effect on the price. Therefore, over time when Bitcoin attracts more ...


8

This is really asking about basic trading economics: if I have some new product X, what price does it have? I can set a price and see if anyone buys it. If not, I might lower the price or auction it to see what someone might pay for it. That is the starting value, but it doesn't really mean much as it hasn't been field-tested (so to speak). If others think ...


8

If you have 0.1 BTC and the Bitcoin price is $10,000, it is worth $1000. If the Bitcoin price becomes $20,000 you will still have 0.1 BTC but it will be worth $2000.


7

For the scenario of a retail or ecommerce purchase, one approach is to have an expiration on the price quotes. For example, when a merchant uses BitPay, the invoice is good for 15 minutes. If the funds aren't received, then the payment is recalculated as-of the time it arrives and if it overpaid, the customer gets a refund and if it was underpaid the ...


7

The upper boundary for energy usage can be described with a function of the profit and energy costs. Miners won't ever pay more for energy than they get from profits. The actual energy usage formula will also have to count for the hardware costs. The formula will look something like this : max energy usage = (profit - hardware costs) / energy cost per unit ...


7

Bitcoin does not have one single buy and sell price. Bitcoins are exchanged on many different exchanges, each keeping track of their own market price. However, BitcoinCharts.com has a useful API that summarises many of the largest exchanges according to their trading volume. You could use that to display the Bitcoin price on your website.


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