# Simple ERC20 token example **URL:** \ **Category:** Guides and Tutorials\ **Created:** [November 5, 2020, 12:43am UTC](https://forum.openzeppelin.com/t/simple-erc20-token-example/4403 "2020-11-05T00:43:36Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![abcoathup](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.openzeppelin.com/abcoathup/32/415_2.png) [@abcoathup](https://forum.openzeppelin.com/u/abcoathup)\ **Post date:** [November 5, 2020, 12:43am UTC](https://forum.openzeppelin.com/t/simple-erc20-token-example/4403/1 "2020-11-05T00:43:36Z")
# Simple ERC20 token example. ⚠ The following code has not been tested nor audited. Seek appropriate advice on **regulatory compliance** and your solution should have appropriate **testing** and **auditing** Recommend reading: [Points to consider when creating a fungible token (ERC20, ERC777)](https://forum.openzeppelin.com/t/points-to-consider-when-creating-a-fungible-token-erc20-erc777/2915) ❗ There is an open issue to add a fixed supply ERC20 preset: [https://github.com/OpenZeppelin/openzeppelin-contracts/issues/2377](https://github.com/OpenZeppelin/openzeppelin-contracts/issues/2377) This example smart contract merely sets a name, symbol and intial supply. All tokens are pre-assigned to the creator using the internal mint function. ## SimpleToken.sol ```auto // contracts/SimpleToken.sol // SPDX-License-Identifier: MIT pragma solidity ^0.6.2; import "@openzeppelin/contracts/token/ERC20/ERC20.sol"; /** * @title SimpleToken * @dev Very simple ERC20 Token example, where all tokens are pre-assigned to the creator. * Note they can later distribute these tokens as they wish using `transfer` and other * `ERC20` functions. * Based on https://github.com/OpenZeppelin/openzeppelin-contracts/blob/v2.5.1/contracts/examples/SimpleToken.sol */ contract SimpleToken is ERC20 { /** * @dev Constructor that gives msg.sender all of existing tokens. */ constructor( string memory name, string memory symbol, uint256 initialSupply ) public ERC20(name, symbol) { _mint(msg.sender, initialSupply); } } ``` ## Migration (Truffle) `2_deploy.js` ```auto // migrations/2_deploy.js const SimpleToken = artifacts.require('SimpleToken'); module.exports = async function (deployer) { await deployer.deploy(SimpleToken, 'SimpleToken', 'SIM', '10000000000000000000000'); }; ``` ## Test ### SimpleToken.test.js ```auto // test/SimpleToken.test.js // SPDX-License-Identifier: MIT // Based on https://github.com/OpenZeppelin/openzeppelin-solidity/blob/v2.5.1/test/examples/SimpleToken.test.js const { expect } = require('chai'); // Import utilities from Test Helpers const { BN, expectEvent, expectRevert, constants } = require('@openzeppelin/test-helpers'); // Load compiled artifacts const SimpleToken = artifacts.require('SimpleToken'); // Start test block contract('SimpleToken', function ([creator, other]) { const NAME = 'SimpleToken'; const SYMBOL = 'SIM'; const TOTAL_SUPPLY = new BN('10000000000000000000000'); beforeEach(async function () { this.token = await SimpleToken.new(NAME, SYMBOL, TOTAL_SUPPLY, { from: creator }); }); it('retrieve returns a value previously stored', async function () { // Use large integer comparisons expect(await this.token.totalSupply()).to.be.bignumber.equal(TOTAL_SUPPLY); }); it('has a name', async function () { expect(await this.token.name()).to.be.equal(NAME); }); it('has a symbol', async function () { expect(await this.token.symbol()).to.be.equal(SYMBOL); }); it('assigns the initial total supply to the creator', async function () { expect(await this.token.balanceOf(creator)).to.be.bignumber.equal(TOTAL_SUPPLY); }); }); ``` ## Crowdsale If you are looking for a crowdsale example, see: [Simple ERC20 Crowdsale](https://forum.openzeppelin.com/t/simple-erc20-crowdsale/4863). ---
**Author:** ![crypto\_economics](https://avatars.discourse-cdn.com/v4/letter/c/ed8c4c/32.png) [@crypto\_economics](https://forum.openzeppelin.com/u/crypto_economics)\ **Post date:** [November 5, 2020, 3:20pm UTC](https://forum.openzeppelin.com/t/simple-erc20-token-example/4403/2 "2020-11-05T15:20:34Z")
@abcoathup this is great! I actually managed to successfully write 5 tests last night after 10 painful days of mental brincsmanship. Your example is extremely helpul – i will take a good look at these. Thank you so much!! ---
**Author:** ![MaxflowO2](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.openzeppelin.com/maxflowo2/32/8022_2.png) [@MaxflowO2](https://forum.openzeppelin.com/u/MaxflowO2)\ **Post date:** [August 7, 2021, 2:00am UTC](https://forum.openzeppelin.com/t/simple-erc20-token-example/4403/4 "2021-08-07T02:00:16Z")
Tried this, caught the ^0.8.0 error... Now throws a constructor error.. ---
**Author:** ![Skyge](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.openzeppelin.com/skyge/32/343_2.png) [@Skyge](https://forum.openzeppelin.com/u/Skyge)\ **Post date:** [August 7, 2021, 2:14am UTC](https://forum.openzeppelin.com/t/simple-erc20-token-example/4403/5 "2021-08-07T02:14:00Z")
Hi, welcome! 👋 > [@abcoathup](#): > > `pragma solidity ^0.6.2;` The case that shows above uses the compiler version of `0.6.x`, but the latest version of the dependency `@openzeppelin/contracts` uses `0.8.x`, so I think you should run this command to install a right dependency: ```auto npm i @openzeppelin/contracts@3.4.0 ``` ---
**Author:** ![MaxflowO2](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.openzeppelin.com/maxflowo2/32/8022_2.png) [@MaxflowO2](https://forum.openzeppelin.com/u/MaxflowO2)\ **Post date:** [August 7, 2021, 2:23am UTC](https://forum.openzeppelin.com/t/simple-erc20-token-example/4403/6 "2021-08-07T02:23:47Z")
```auto // contracts/SimpleToken.sol // SPDX-License-Identifier: MIT pragma solidity ^0.8.0; import "@openzeppelin/contracts/token/ERC20/ERC20.sol"; /** * @title SimpleToken * @dev Very simple ERC20 Token example, where all tokens are pre-assigned to the creator. * Note they can later distribute these tokens as they wish using `transfer` and other * `ERC20` functions. * Based on https://github.com/OpenZeppelin/openzeppelin-contracts/blob/v2.5.1/contracts/examples/SimpleToken.sol */ contract SimpleToken is ERC20 { /** * @dev Constructor that gives msg.sender all of existing tokens. */ constructor(string memory name, string memory symbol, uint256 initialSupply) ERC20(name, symbol) { _mint(msg.sender, initialSupply); } } ``` There's the update for you also launched on Rinkeby... > **[SimpleToken (SIM) Token Tracker | Etherscan](https://rinkeby.etherscan.io/token/0x3bd7d345b9eb37cee32ac42b64bb5601eda93a7f#readContract)** > > SimpleToken (SIM) Token Tracker on Etherscan shows the price of the Token $0.00, total supply 10,000, number of holders 1 and updated information of the token. The token tracker page also shows the analytics and historical data. ---
**Author:** ![ffernandomaximo](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.openzeppelin.com/ffernandomaximo/32/9570_2.png) [@ffernandomaximo](https://forum.openzeppelin.com/u/ffernandomaximo)\ **Post date:** [October 14, 2021, 8:10am UTC](https://forum.openzeppelin.com/t/simple-erc20-token-example/4403/7 "2021-10-14T08:10:11Z")
Did you start your local blockchain? I was getting the same error, then configured the truffle-config.js and started Ganache. ---
**Author:** ![MaxflowO2](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.openzeppelin.com/maxflowo2/32/8022_2.png) [@MaxflowO2](https://forum.openzeppelin.com/u/MaxflowO2)\ **Post date:** [October 15, 2021, 5:20am UTC](https://forum.openzeppelin.com/t/simple-erc20-token-example/4403/8 "2021-10-15T05:20:50Z")
Yeah I got this, tossed it on Rinkeby before the faucet shut off. Just needed to update the constructor to the 0.8.x standards. ---
**Author:** ![parin13](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.openzeppelin.com/parin13/32/231_2.png) [@parin13](https://forum.openzeppelin.com/u/parin13)\ **Post date:** [September 9, 2022, 10:19am UTC](https://forum.openzeppelin.com/t/simple-erc20-token-example/4403/9 "2022-09-09T10:19:33Z")
this : ` new BN('10000000000000000000000');` still gives error !! ``` Error: Number can only safely store up to 53 bits ```