diff --git a/.npmrc b/.npmrc
new file mode 100644
index 0000000..41a3429
--- /dev/null
+++ b/.npmrc
@@ -0,0 +1,2 @@
+unsafe-perm = true
+package-lock=false
diff --git a/README.md b/README.md
index e91aa27..89e22ba 100644
--- a/README.md
+++ b/README.md
@@ -44,7 +44,7 @@ const EthCrypto = require('eth-crypto');
 
 - [createIdentity()](#createidentity)
 - [publicKeyByPrivateKey()](#publickeybyprivatekey)
-- [addressByPublicKey()](#addressbypublickey)
+- [publicKey.toAddress()](#addressbypublickey)
 - [sign()](#sign)
 - [recover()](#recover)
 - [recoverPublicKey()](#recoverpublickey)
@@ -78,17 +78,39 @@ Derives the publicKey from a privateKey and returns it as hex-string.
   // > 'bf1cc3154424dc22191941d9f4f50b063a2b663a2337e5548abea633c1d06ece...'
 ```
 
-### addressByPublicKey()
+### publicKey.toAddress()
 
 Derives the ethereum-address from the publicKey.
 
 ```javascript
-  const address = EthCrypto.addressByPublicKey(
+  const address = EthCrypto.publicKey.toAddress(
       'bf1cc3154424dc22191941d9f4f50b063a2b663a2337e5548abea633c1d06ece...'
   );
   // > '0x3f243FdacE01Cfd9719f7359c94BA11361f32471'
 ```
 
+### publicKey.compress()
+
+Compresses an uncompressed publicKey.
+
+```javascript
+  const address = EthCrypto.publicKey.compress(
+      '04a34d6aef3eb42335fb3cacb59...'
+  );
+  // > '03a34d6aef3eb42335fb3cacb59478c0b44c0bbeb8bb4ca427dbc7044157a5d24b' // compressed keys start with '02' or '03'
+```
+
+### publicKey.decompress()
+
+Decompresses a compressed publicKey.
+
+```javascript
+  const address = EthCrypto.publicKey.decompress(
+      '03a34d6aef3eb42335fb3c...'
+  );
+  // > 'a34d6aef3eb42335fb3cacb5947' // non-compressed keys start with '04' or no prefix
+```
+
 ### sign()
 
 Signs the hash with the privateKey. Returns the signature as hex-string.
diff --git a/package.json b/package.json
index a68bfbc..92947c0 100644
--- a/package.json
+++ b/package.json
@@ -88,6 +88,6 @@
     "ethereumjs-tx": "1.3.4",
     "ethereumjs-util": "5.1.5",
     "secp256k1": "3.5.0",
-    "web3": "1.0.0-beta.30"
+    "web3": "1.0.0-beta.34"
   }
 }
diff --git a/src/address-by-public-key.js b/src/address-by-public-key.js
deleted file mode 100644
index e29531d..0000000
--- a/src/address-by-public-key.js
+++ /dev/null
@@ -1,15 +0,0 @@
-import EthUtil from 'ethereumjs-util';
-import {
-    web3
-} from './util';
-
-/**
- * generates the ethereum-adress of the publicKey
- * We create the checksum-adress which is case-sensitive
- * @returns {string} address
- */
-export default function addressByPublicKey(publicKey) {
-    const addressBuffer = EthUtil.pubToAddress(new Buffer(publicKey, 'hex'));
-    const checkSumAdress = web3.utils.toChecksumAddress(addressBuffer.toString('hex'));
-    return checkSumAdress;
-}
diff --git a/src/create-identity.js b/src/create-identity.js
index a5f5360..53bbc6d 100644
--- a/src/create-identity.js
+++ b/src/create-identity.js
@@ -1,20 +1,13 @@
-import {
-    web3
-} from './util';
 import publicKeyByPrivateKey from './public-key-by-private-key';
 
+import Account from 'eth-lib/lib/account';
+
 /**
  * creates a new object with
  * private-, public-Key and address
  */
 export default function createIdentity() {
-    const account = web3.eth.accounts.create();
-
-    const identity = {
-        address: account.address,
-        privateKey: account.privateKey,
-        publicKey: publicKeyByPrivateKey(account.privateKey)
-    };
-
+    const identity = Account.create();
+    identity.publicKey = publicKeyByPrivateKey(identity.privateKey);
     return identity;
 }
diff --git a/src/encrypt-with-public-key.js b/src/encrypt-with-public-key.js
index 95723e7..bbacab8 100644
--- a/src/encrypt-with-public-key.js
+++ b/src/encrypt-with-public-key.js
@@ -1,7 +1,13 @@
 import eccrypto from 'eccrypto';
+import {
+    decompress
+} from './public-key';
 
 export default async function encryptWithPublicKey(publicKey, message) {
 
+    // ensure its an uncompressed publicKey
+    publicKey = decompress(publicKey);
+
     // re-add the compression-flag
     const pubString = '04' + publicKey;
 
diff --git a/src/hash.js b/src/hash.js
index 481dc20..d7b1da6 100644
--- a/src/hash.js
+++ b/src/hash.js
@@ -13,16 +13,3 @@ export function keccak256(params) {
 }
 
 export const SIGN_PREFIX = '\x19Ethereum Signed Message:\n32';
-
-/**
- * hashes the given hash with the web3-prefix
- * '\x19Ethereum Signed Message:\n32'
- */
-export function prefixedHash(hash) {
-    if (!web3.utils.isHexStrict(hash))
-        throw new Error('EthCrypto.hash.prefixedHash(): please insert an hash');
-    return web3.eth.accounts.hashMessage({
-        type: 'bytes32',
-        value: hash
-    });
-}
diff --git a/src/hex.js b/src/hex.js
index fa32ed3..a9e7e7f 100644
--- a/src/hex.js
+++ b/src/hex.js
@@ -4,10 +4,13 @@
  * @link https://stackoverflow.com/a/40471908/3443137
  */
 
-import * as util from './util';
+import {
+    removeTrailing0x,
+    addTrailing0x
+} from './util';
 
 export function compress(hex, base64 = false) {
-    hex = util.removeTrailing0x(hex);
+    hex = removeTrailing0x(hex);
 
     // if base64:true, we use our own function because it results in a smaller output
     if (base64 === true)
@@ -29,7 +32,7 @@ export function decompress(compressedString, base64 = false) {
     // if base64:true, we use our own function because it results in a smaller output
     if (base64 === true) {
         const ret = new Buffer(compressedString, 'base64').toString('hex');
-        return util.addTrailing0x(ret);
+        return addTrailing0x(ret);
     }
 
     let hex = '';
@@ -38,5 +41,5 @@ export function decompress(compressedString, base64 = false) {
         hex += ((i == 0 ? '' : '000') + compressedString.charCodeAt(i).toString(16)).slice(-4);
     }
     hex = hex.toLowerCase();
-    return util.addTrailing0x(hex);
+    return addTrailing0x(hex);
 }
diff --git a/src/index.js b/src/index.js
index a3c0c07..b731b8e 100644
--- a/src/index.js
+++ b/src/index.js
@@ -1,5 +1,6 @@
-import addressByPublicKey from './address-by-public-key';
+
 import createIdentity from './create-identity';
+import * as publicKey from './public-key';
 import decryptWithPrivateKey from './decrypt-with-private-key';
 import encryptWithPublicKey from './encrypt-with-public-key';
 import publicKeyByPrivateKey from './public-key-by-private-key';
@@ -15,8 +16,8 @@ import * as vrs from './vrs';
 import * as util from './util';
 
 export {
-    addressByPublicKey,
     createIdentity,
+    publicKey,
     decryptWithPrivateKey,
     encryptWithPublicKey,
     publicKeyByPrivateKey,
@@ -33,8 +34,8 @@ export {
 };
 
 export default {
-    addressByPublicKey,
     createIdentity,
+    publicKey,
     decryptWithPrivateKey,
     encryptWithPublicKey,
     publicKeyByPrivateKey,
diff --git a/src/public-key.js b/src/public-key.js
new file mode 100644
index 0000000..8a694c8
--- /dev/null
+++ b/src/public-key.js
@@ -0,0 +1,48 @@
+import {
+    publicKeyConvert
+} from 'secp256k1';
+import ethUtil from 'ethereumjs-util';
+
+export function compress(startsWith04) {
+
+    // add trailing 04 if not done before
+    const testBuffer = new Buffer(startsWith04, 'hex');
+    if (testBuffer.length === 64) startsWith04 = '04' + startsWith04;
+
+
+    return publicKeyConvert(
+        new Buffer(startsWith04, 'hex'),
+        true
+    ).toString('hex');
+};
+
+export function decompress(startsWith02Or03) {
+
+    // if already decompressed an not has trailing 04
+    const testBuffer = new Buffer(startsWith02Or03, 'hex');
+    if (testBuffer.length === 64) startsWith02Or03 = '04' + startsWith02Or03;
+
+    let decompressed = publicKeyConvert(
+        new Buffer(startsWith02Or03, 'hex'),
+        false
+    ).toString('hex');
+
+    // remove trailing 04
+    decompressed = decompressed.substring(2);
+    return decompressed;
+};
+
+/**
+ * generates the ethereum-adress of the publicKey
+ * We create the checksum-adress which is case-sensitive
+ * @returns {string} address
+ */
+export function toAddress(publicKey) {
+
+    // normalize key
+    publicKey = decompress(publicKey);
+
+    const addressBuffer = ethUtil.pubToAddress(new Buffer(publicKey, 'hex'));
+    const checkSumAdress = ethUtil.toChecksumAddress(addressBuffer.toString('hex'));
+    return checkSumAdress;
+}
diff --git a/src/recover-public-key.js b/src/recover-public-key.js
index 19ddcda..a3ab403 100644
--- a/src/recover-public-key.js
+++ b/src/recover-public-key.js
@@ -1,7 +1,11 @@
-import * as secp256k1 from 'secp256k1';
+import {
+    recover
+} from 'secp256k1';
 
 import * as vrs from './vrs';
-import * as util from './util';
+import {
+    removeTrailing0x
+} from './util';
 
 
 /**
@@ -15,12 +19,12 @@ export default function recoverPublicKey(signature, hash) {
 
 
     let sigOnly = signature.substring(0, signature.length - 1);
-    sigOnly = util.removeTrailing0x(sigOnly);
+    sigOnly = removeTrailing0x(sigOnly);
 
     const recoveryNumber = vals.v === '0x1c' ? 1 : 0;
 
-    let pubKey = secp256k1.recover(
-        new Buffer(util.removeTrailing0x(hash), 'hex'),
+    let pubKey = recover(
+        new Buffer(removeTrailing0x(hash), 'hex'),
         new Buffer(sigOnly, 'hex'),
         recoveryNumber,
         false
diff --git a/src/recover.js b/src/recover.js
index 3da86ce..26880d9 100644
--- a/src/recover.js
+++ b/src/recover.js
@@ -1,5 +1,7 @@
 import recoverPublicKey from './recover-public-key';
-import addressByPublicKey from './address-by-public-key';
+import {
+    toAddress as addressByPublicKey
+} from './public-key';
 
 /**
  * returns the adress with which the messageHash was signed
diff --git a/src/sign-transaction.js b/src/sign-transaction.js
index cbdac49..ea0c821 100644
--- a/src/sign-transaction.js
+++ b/src/sign-transaction.js
@@ -1,6 +1,8 @@
 import Tx from 'ethereumjs-tx';
 import publicKeyByPrivateKey from './public-key-by-private-key';
-import addressByPublicKey from './address-by-public-key';
+import {
+    toAddress as addressByPublicKey
+} from './public-key';
 
 export default function signTransaction(
     rawTx,
diff --git a/src/sign.js b/src/sign.js
index e63ed21..98d2fb7 100644
--- a/src/sign.js
+++ b/src/sign.js
@@ -1,5 +1,10 @@
-import * as secp256k1 from 'secp256k1';
-import * as util from './util';
+import {
+    sign as secp256k1_sign
+} from 'secp256k1';
+import {
+    addTrailing0x,
+    removeTrailing0x
+} from './util';
 
 /**
  * signs the given message
@@ -9,13 +14,13 @@ import * as util from './util';
  * @return {string} hexString
  */
 export default function sign(privateKey, hash) {
-    hash = util.addTrailing0x(hash);
+    hash = addTrailing0x(hash);
     if (hash.length !== 66)
         throw new Error('EthCrypto.sign(): Can only sign hashes, given: ' + hash);
 
-    const sigObj = secp256k1.sign(
-        new Buffer(util.removeTrailing0x(hash), 'hex'),
-        new Buffer(util.removeTrailing0x(privateKey), 'hex')
+    const sigObj = secp256k1_sign(
+        new Buffer(removeTrailing0x(hash), 'hex'),
+        new Buffer(removeTrailing0x(privateKey), 'hex')
     );
 
     const recoveryId = sigObj.recovery === 1 ? '1c' : '1b';
diff --git a/test/unit.test.js b/test/unit.test.js
index 70e1cc3..edfdb0c 100644
--- a/test/unit.test.js
+++ b/test/unit.test.js
@@ -36,21 +36,6 @@ describe('unit.test.js', () => {
             });
         });
     });
-    describe('.addressByPublicKey()', () => {
-        describe('positive', () => {
-            it('should generate the correct address', () => {
-                const address = EthCrypto.addressByPublicKey(TEST_DATA.publicKey);
-                assert.equal(address, TEST_DATA.address);
-            });
-        });
-        describe('negative', () => {
-            assert.throws(
-                () => EthCrypto.addressByPublicKey(
-                    AsyncTestUtil.randomString(12)
-                )
-            );
-        });
-    });
     describe('.sign()', () => {
         describe('positive', () => {
             it('should sign the data', () => {
@@ -116,6 +101,20 @@ describe('unit.test.js', () => {
                 assert.equal(typeof encrypted.ciphertext, 'string');
                 assert.equal(typeof encrypted.mac, 'string');
             });
+            it('should also work with compressed keys', async () => {
+                const message = AsyncTestUtil.randomString(12);
+                const ident = EthCrypto.createIdentity();
+                const compressed = EthCrypto.publicKey.compress(ident.publicKey);
+                const encrypted = await EthCrypto.encryptWithPublicKey(
+                    compressed,
+                    message
+                );
+                const decrypted = await EthCrypto.decryptWithPrivateKey(
+                    ident.privateKey,
+                    encrypted
+                );
+                assert.equal(decrypted, message);
+            });
         });
         describe('negative', () => {
             it('should throw when non-key given', async () => {
@@ -124,7 +123,8 @@ describe('unit.test.js', () => {
                     () => EthCrypto.encryptWithPublicKey(
                         AsyncTestUtil.randomString(12),
                         message
-                    )
+                    ),
+                    'RangeError'
                 );
             });
         });
@@ -146,6 +146,72 @@ describe('unit.test.js', () => {
         });
         describe('negative', () => {});
     });
+    describe('.publicKey', () => {
+        describe('.compress()', () => {
+            it('should compress the key', () => {
+                const uncompressed = 'a34d6aef3eb42335fb3cacb59478c0b44c0bbeb8bb4ca427dbc7044157a5d24b4adf14868d8449c9b3e50d3d6338f3e5a2d3445abe679cddbe75cb893475806f';
+                const compressed = EthCrypto.publicKey.compress(uncompressed);
+                assert.equal(typeof compressed, 'string');
+                assert.ok(compressed.startsWith('03'));
+            });
+            it('should also work with trailing 04', () => {
+                const uncompressed = '04a34d6aef3eb42335fb3cacb59478c0b44c0bbeb8bb4ca427dbc7044157a5d24b4adf14868d8449c9b3e50d3d6338f3e5a2d3445abe679cddbe75cb893475806f';
+                const compressed = EthCrypto.publicKey.compress(uncompressed);
+                assert.equal(typeof compressed, 'string');
+                assert.ok(compressed.startsWith('03'));
+            });
+            it('should also work when compressed already given', () => {
+                const uncompressed = '03a34d6aef3eb42335fb3cacb59478c0b44c0bbeb8bb4ca427dbc7044157a5d24b';
+                const compressed = EthCrypto.publicKey.compress(uncompressed);
+                assert.equal(typeof compressed, 'string');
+                assert.ok(compressed.startsWith('03'));
+            });
+        });
+        describe('.decompress()', () => {
+            it('should decompress', () => {
+                const compressed = '03a34d6aef3eb42335fb3cacb59478c0b44c0bbeb8bb4ca427dbc7044157a5d24b';
+                const uncompressed = EthCrypto.publicKey.decompress(compressed);
+                assert.equal(typeof uncompressed, 'string');
+                const buf = new Buffer(uncompressed, 'hex');
+                assert.equal(buf.length, 64);
+            });
+            it('should work when already uncompressed', () => {
+                const compressed = '04a34d6aef3eb42335fb3cacb59478c0b44c0bbeb8bb4ca427dbc7044157a5d24b4adf14868d8449c9b3e50d3d6338f3e5a2d3445abe679cddbe75cb893475806f';
+                const uncompressed = EthCrypto.publicKey.decompress(compressed);
+                assert.equal(typeof uncompressed, 'string');
+                const buf = new Buffer(uncompressed, 'hex');
+                assert.equal(buf.length, 64);
+            });
+            it('should work when already uncompressed (no04)', () => {
+                const compressed = 'a34d6aef3eb42335fb3cacb59478c0b44c0bbeb8bb4ca427dbc7044157a5d24b4adf14868d8449c9b3e50d3d6338f3e5a2d3445abe679cddbe75cb893475806f';
+                const uncompressed = EthCrypto.publicKey.decompress(compressed);
+                assert.equal(typeof uncompressed, 'string');
+                const buf = new Buffer(uncompressed, 'hex');
+                assert.equal(buf.length, 64);
+            });
+        });
+        describe('.toAddress()', () => {
+            describe('positive', () => {
+                it('should generate the correct address', () => {
+                    const address = EthCrypto.publicKey.toAddress(TEST_DATA.publicKey);
+                    assert.equal(address, TEST_DATA.address);
+                });
+                it('should work with compressed key', () => {
+                    const ident = EthCrypto.createIdentity();
+                    const compressed = EthCrypto.publicKey.compress(ident.publicKey);
+                    const address = EthCrypto.publicKey.toAddress(compressed);
+                    assert.equal(address, ident.address);
+                });
+            });
+            describe('negative', () => {
+                assert.throws(
+                    () => EthCrypto.publicKey.toAddress(
+                        AsyncTestUtil.randomString(12)
+                    )
+                );
+            });
+        });
+    });
     describe('.signTransaction()', () => {
         describe('positive', () => {
             it('should sign our transaction', () => {
diff --git a/typings/index.d.ts b/typings/index.d.ts
index ea5376e..0b025f7 100644
--- a/typings/index.d.ts
+++ b/typings/index.d.ts
@@ -7,8 +7,13 @@ export function createIdentity(): {
     address: string
 };
 
+export type publicKey = {
+    compress(publicKey: string): string;
+    decompress(publicKey: string): string;
+    toAddress(publicKey: string): string;
+};
+
 export function publicKeyByPrivateKey(privateKey: string): string;
-export function addressByPublicKey(publicKey: string): string;
 
 export type Signature = {
     v: string,
@@ -67,8 +72,6 @@ export type TypedValue = {
 
 export type hash = {
     keccak256(params: TypedValue[]): string;
-    prefixedHash(msg: string): string;
-    SIGN_PREFIX: string;
 };
 
 export type util = {
@@ -86,8 +89,8 @@ export type hex = {
 export function publicKeyToAddress(publicKey: string): string;
 
 declare const _default: {
-    addressByPublicKey,
     createIdentity,
+    publicKey,
     decryptWithPrivateKey,
     encryptWithPublicKey,
     publicKeyByPrivateKey,