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18 votes

what is the difference between hard cap and soft cap in ethereum ICO

A hard cap is defined as the maximum amount a crowdsale will receive. Most projects set a very high cap that is unlikely to happen. Only very famous projects like Status or Brave browser have reached ...
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18 votes
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What are the popular API to get current exchange rates for Ethereum to USD

I recommend CryptoCompare: https://www.cryptocompare.com/api/ Example: GET https://min-api.cryptocompare.com/data/price?fsym=ETH&tsyms=BTC,USD,EUR {"BTC":0.1048,"USD":858.99,"EUR":662.93}
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17 votes
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Is there length limits on Token Symbols?

I used the CoinMarketCap API to pull down a list of all registered currencies and assets (so not just ERC-20 tokens... ), and fed it into a quick Python script to count the number of occurrences of ...
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11 votes
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What is minting? how is minting prevented after ICO?

Smart contracts are computer programs. You can code almost any business logic you want in them. That includes the business logic for minting new coins. The trust of your ICO contributors is the ...
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7 votes

How can I split my Contract up into different smaller ones?

You have to do something like this: Token.sol // This should be an abstract interface without implementation contract Token { function mint(address _to, uint _amount) public returns (bool); // ...
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7 votes
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Crowdsales: non-mintable tokens vs mintable tokens (with hard cap)

Yup, its the same - but if you give 10 developers the same problem you could get 10 different ways of solving it. Its interesting though, if you think about it - Ethereum actually rewards users of ...
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  • 586
6 votes

ICO crypto-currencies accepted during the sale: ETH, BTC, or even fiat?

Yes, ethereum smart contract can only accept ether. So if one wants to use Bitcoin to buy ethereum tokens, then you need to do something to let it happen. I have seen different approaches to this ...
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6 votes
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Where can I find a smart contract code for an ICO?

OpenZeppelin has a GitHub repo with peer-reviewed open source contracts for tokens and crowdsales. They're a good source to see working ICO contracts. The examples include refundable crowdsales, ...
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6 votes
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What does it really mean to burn tokens?

You are partially correct. You could ether send tokens to an address with an unknown private key, or you could just delete them, if a function like that was implemented when the contract was created. ...
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5 votes

how to setup multicurrency ICO / Crowdsale

An Ethereum contract cannot directly interact with other blockchains. You have to use a service like BTC Relay, their project on github.
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5 votes
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How to issue tradable tokens?

First your investors will want a clearly defined issuance policy, so they can better know how to value your token. If you can arbitrarily issue tokens then their tokens will be losing value when extra ...
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  • 29.2k
5 votes

What are the popular API to get current exchange rates for Ethereum to USD

https://developers.coinbase.com/api/v2#exchange-rates By coinbase ,I think best api for exchange rates with accurate data example for ethereum: https://api.coinbase.com/v2/exchange-rates?currency=ETH
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5 votes

all these ICOs tokens offers to finance new startups are under ethereum technology?

Possibly off-topic... all these ICOs tokens offers to finance new startups are under ethereum technology? Not all of them are on Ethereum. Here's a count of the number of tokens - each ...
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4 votes
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Best practices on Token ICO launch

I can add to your list the Open Zeppelin. It contains some secure contracts with best practices. We will use some of their contracts during our project's called "Jincor" ICO Returning to your ...
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  • 196
4 votes

Is it possible to create ICO crowdsale seamlessly accepting multiple assets?

This is only a partial answer to your question. One issue you would face is that deposits by people who buy your tokens with BTC or any other cryptocurrency besides ETH would have to be credited ...
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  • 2,249
4 votes

How can I create a Dashboard for my Ethereum ICO investors to track their Tokens

I would suggest you using NodeJS and web3js library to interact with ethereum. It would not be really hard to get into NodeJS of you are a web developer. My team and I opened a source code of the ...
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  • 196
4 votes

Is there length limits on Token Symbols?

This same code for py 3.10 and new API coinmarket : from requests import Request, Session from requests.exceptions import ConnectionError, Timeout, TooManyRedirects from collections import Counter ...
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  • 41
4 votes
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Paid Ether to ICO but tx failed, however the Ether is not returning to my wallet!

You've only ever had three transactions. Two debiting your account and one crediting. 7.06 - 1.001565608 - 0.0004895(gas used from failed transaction) = 6.057944892 Your account balance at the ...
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  • 1,540
4 votes
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How to use ICO tokens to pay for ethereum dapp smart contract transactions?

The tokens someone owns is just a balance in your Token smart contract. So, How will my users with ICO tokens pay for dApp transactions fee on Ethereum, should I send them in ether or token ? ...
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  • 7,216
4 votes
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Pausable Contract in OpenZeppelin

The Pausable contract you're inheriting from just adds pause and unpause, which updates a state variable paused. But that's all it does by itself. You'll need to use the modifiers whenPaused and ...
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  • 26.2k
4 votes

How to limit the ICO contract to 49% of the total supply?

Following the logic of your code, you add this constraint into your fallback function. Replace balances[fundsWallet] = balances[fundsWallet].sub(tokenAmount); with uint256 newBalance = balances[...
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  • 446
4 votes
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Why are ICO startups claiming to build blockchains with different functionality, but yet are using Ethereum?

So a lot of these companies are separating the ERC 20 token being sold during the ICO process and their actually technology. Think of the ERC 20 token as contract to be exchange for the true currency ...
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  • 597
3 votes

What is "issuer-backed assets" in ethereum white paper?

An issuer-backed asset is one in which the asset (digital token) is backed (supported) by the issuing party. With the US gold standard, the US government promised to give the holder of US currency a ...
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  • 6,530
3 votes

What is "issuer-backed assets" in ethereum white paper?

The passage you quoted above is referring to the concept of a stable coin. Stable coins are crypto-assets which are tied to, or "pegged," to some other asset as a way to maintain a stable value and ...
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  • 350
3 votes

Where to find ICO contract with linear / logarithmic decrease?

Let's suppose we have M the maximum amount of tokens to sell, I the initial price of each token and F the final price of each token. Let's call f the function that gives the price of each token, we ...
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  • 29.2k
3 votes

When ICO doesn't take place?

It really depends on the company and how they make their contracts for token distribution. If some have a minimum investment goal, ideally they would code in their smart contracts to refund all of ...
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  • 31
3 votes

How many ethereum blocks are mined in a day?End and Startblock specification

The block time in Ethereum is about 15 seconds on average, and that does not change over time very much. Thus, there will always be about 5760 blocks per day.
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3 votes
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Can I use ICO (Initial Coin Offering) to fund for a non-blockchain project?

It's possible to treat an ICO as nothing more than a funding mechanism, yes. Filecoin, for example, ran an ICO on the Ethereum blockchain, but will be operating on a separate chain, indicating that ...
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  • 166
3 votes
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Is it possible to reissue the same token symbol after ICO?

Symbol and Names are not unique. As a matter of fact if you do a search on etherscan you will notice there can be several tokens with the same name or symbol. The only thing that makes them unique or ...
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  • 7,216
3 votes
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ICO contract transfers

Usually, the raising of funds through a crowdsale is achieved through a different contract to the one implementing the ERC20 standards - this separation of concerns is a good software development ...
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  • 2,418

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