eth-crypto/src/public-key-by-private-key.js

Cryptographic functions for ethereum and how to use them with web3 and solidity

import {
    privateToPublic,
    toBuffer
} from 'ethereumjs-util';
import {
    addLeading0x
} from './util';

/**
 * Generate publicKey from the privateKey.
 * This creates the uncompressed publicKey,
 * where 04 has stripped from left
 * @returns {string}
 */
export function publicKeyByPrivateKey(privateKey) {
    privateKey = addLeading0x(privateKey);
    const publicKeyBuffer = privateToPublic(toBuffer(privateKey));
    return publicKeyBuffer.toString('hex');
}