diff --git a/src/utils/bignumber.ts b/src/utils/bignumber.ts
index 7abc0fdf2b..a1a5c75a1c 100644
--- a/src/utils/bignumber.ts
+++ b/src/utils/bignumber.ts
@@ -1,18 +1,10 @@
 /**
  * Big Number Helpers
  * @module @aeternity/aepp-sdk/es/utils/bignumber
- * @example import { parseBigNumber, isBigNumber, ceil } from '@aeternity/aepp-sdk/es/utils/bignumber'
+ * @example import { isBigNumber, ceil } from '@aeternity/aepp-sdk/es/utils/bignumber'
  */
 import BigNumber from 'bignumber.js'
 
-/**
- * Convert number to string
- * @param {String|Number|BigNumber} number number to convert
- * @return {String}
- */
-export const parseBigNumber = (number: string | number | BigNumber): string =>
-  new BigNumber(number.toString()).toString(10)
-
 /**
  * Check if value is BigNumber, Number or number string representation
  * @param {String|Number|BigNumber} number number to convert
diff --git a/src/utils/crypto.js b/src/utils/crypto.js
index a73908a844..84687ef380 100644
--- a/src/utils/crypto.js
+++ b/src/utils/crypto.js
@@ -26,7 +26,7 @@ import nacl from 'tweetnacl'
 import aesjs from 'aes-js'
 import shajs from 'sha.js'
 
-import { str2buf, toBytes } from './bytes'
+import { str2buf } from './bytes'
 import { decode } from '../tx/builder/helpers'
 import { hash } from './crypto-ts'
 import { InvalidChecksumError, MessageLimitError } from './errors'
@@ -63,16 +63,6 @@ export function isAddressValid (address, prefix = 'ak') {
   }
 }
 
-/**
- * Parse decimal address and return base58Check encoded address with prefix 'ak'
- * @rtype (input: String) => address: String
- * @param {String} decimalAddress - Address
- * @return {String} address
- */
-export function addressFromDecimal (decimalAddress) {
-  return aeEncodeKey(toBytes(decimalAddress, true))
-}
-
 /**
  * Calculate SHA256 hash of `input`
  * @rtype (input: String) => hash: String
@@ -284,19 +274,6 @@ export function verifyMessage (str, signature, publicKey) {
   return verify(messageToHash(str), signature, publicKey)
 }
 
-/**
- * æternity readable public keys are the base58-encoded public key, prepended
- * with 'ak_'
- * @rtype (binaryKey: Buffer) => String
- * @param {Buffer} binaryKey - Key to encode
- * @return {String} Encoded key
- */
-export function aeEncodeKey (binaryKey) {
-  const publicKeyBuffer = Buffer.from(binaryKey, 'hex')
-  const pubKeyAddress = encodeBase58Check(publicKeyBuffer)
-  return `ak_${pubKeyAddress}`
-}
-
 /**
  * Check key pair for validity
  *
diff --git a/test/unit/amount-formatter.ts b/test/unit/amount-formatter.ts
index 9da97e428f..3c1df28296 100644
--- a/test/unit/amount-formatter.ts
+++ b/test/unit/amount-formatter.ts
@@ -20,21 +20,20 @@ import { expect } from 'chai'
 import BigNumber from 'bignumber.js'
 import '..'
 import { AE_AMOUNT_FORMATS, formatAmount, toAe, toAettos } from '../../src/utils/amount-formatter'
-import { parseBigNumber } from '../../src/utils/bignumber'
 import { InvalidDenominationError, IllegalArgumentError } from '../../src/utils/errors'
 
 describe('Amount Formatter', function () {
-  it('to aettos', async () => {
+  it('to aettos', () => {
     [
-      [1, AE_AMOUNT_FORMATS.AE, 1e18],
-      [10, AE_AMOUNT_FORMATS.AE, 10e18],
-      [100, AE_AMOUNT_FORMATS.AE, 100e18],
-      [10012312, AE_AMOUNT_FORMATS.AE, 10012312e18],
-      [1, AE_AMOUNT_FORMATS.AETTOS, 1]
-    ].forEach(
-      ([v, d, e]) => expect(parseBigNumber(e)).to.be.equal(toAettos(v, { denomination: d.toString() }))
-    )
+      [1, AE_AMOUNT_FORMATS.AE, '1000000000000000000'],
+      [11, AE_AMOUNT_FORMATS.AE, '11000000000000000000'],
+      [111, AE_AMOUNT_FORMATS.AE, '111000000000000000000'],
+      [10012312, AE_AMOUNT_FORMATS.AE, '10012312000000000000000000'],
+      [1, AE_AMOUNT_FORMATS.AETTOS, '1']
+    ].forEach(([v, denomination, e]: [number, string, string]) =>
+      expect(toAettos(v, { denomination })).to.be.equal(e))
   })
+
   it('to Ae', () => {
     [
       [1, AE_AMOUNT_FORMATS.AETTOS, new BigNumber(1).div(1e18)],
@@ -42,10 +41,10 @@ describe('Amount Formatter', function () {
       [100, AE_AMOUNT_FORMATS.AETTOS, new BigNumber(100).div(1e18)],
       [10012312, AE_AMOUNT_FORMATS.AETTOS, new BigNumber(10012312).div(1e18)],
       [1, AE_AMOUNT_FORMATS.AE, 1]
-    ].forEach(
-      ([v, d, e]) => expect(parseBigNumber(e)).to.be.equal(toAe(v, { denomination: d.toString() }))
-    )
+    ].forEach(([v, denomination, e]: [number, string, BigNumber]) =>
+      expect(toAe(v, { denomination })).to.be.equal(e.toString(10)))
   })
+
   it('format', () => {
     [
       [1, AE_AMOUNT_FORMATS.AE, AE_AMOUNT_FORMATS.AETTOS, new BigNumber(1e18)],
@@ -67,17 +66,18 @@ describe('Amount Formatter', function () {
       [1, AE_AMOUNT_FORMATS.NANO_AE, AE_AMOUNT_FORMATS.AETTOS, new BigNumber(1000000000)],
       [1, AE_AMOUNT_FORMATS.FEMTO_AE, AE_AMOUNT_FORMATS.AETTOS, new BigNumber(1000)],
       [1, AE_AMOUNT_FORMATS.NANO_AE, AE_AMOUNT_FORMATS.FEMTO_AE, new BigNumber(1000000)]
-    ].forEach(
-      ([v, dF, dT, e]) => expect(parseBigNumber(e)).to.be.equal(formatAmount(v, { denomination: dF.toString(), targetDenomination: dT.toString() }))
-    )
+    ].forEach(([v, denomination, targetDenomination, e]: [number, string, string, BigNumber]) =>
+      expect(formatAmount(v, { denomination, targetDenomination })).to.be.equal(e.toString(10)))
   })
+
   it('Invalid value', () => {
     [
-      [true, [AE_AMOUNT_FORMATS.AE, AE_AMOUNT_FORMATS.AE], 'Value true is not type of number', IllegalArgumentError],
-      [1, [AE_AMOUNT_FORMATS.AE, 'ASD'], 'Invalid target denomination: ASD', InvalidDenominationError],
-      [1, ['ASD', AE_AMOUNT_FORMATS.AE], 'Invalid denomination: ASD', InvalidDenominationError]
-    ].forEach(([v, [dF, dT], error]: any[]) => {
-      expect(() => formatAmount(v, { denomination: dF, targetDenomination: dT })).to.throw(error)
+      [true, AE_AMOUNT_FORMATS.AE, AE_AMOUNT_FORMATS.AE, IllegalArgumentError, 'Value true is not type of number'],
+      [1, AE_AMOUNT_FORMATS.AE, 'ASD', InvalidDenominationError, 'Invalid target denomination: ASD'],
+      [1, 'ASD', AE_AMOUNT_FORMATS.AE, InvalidDenominationError, 'Invalid denomination: ASD']
+    ].forEach(([v, dF, dT, error, msg]: any[]) => {
+      expect(() => formatAmount(v, { denomination: dF, targetDenomination: dT }))
+        .to.throw(error, msg)
     })
   })
 })
diff --git a/test/unit/tx.js b/test/unit/tx.js
index 26cc9b8341..aa5e3462c8 100644
--- a/test/unit/tx.js
+++ b/test/unit/tx.js
@@ -33,7 +33,6 @@ import {
 } from '../../src/tx/builder/helpers'
 import BigNumber from 'bignumber.js'
 import { toBytes } from '../../src/utils/bytes'
-import { parseBigNumber } from '../../src/utils/bignumber'
 import { buildTx, unpackTx } from '../../src/tx/builder'
 import { NAME_BID_RANGES } from '../../src/tx/builder/schema'
 import {
@@ -49,10 +48,6 @@ describe('Tx', function () {
     return hash.should.be.equal(await commitmentHash('foobar.chain', _salt))
   })
 
-  it('Parse big number', async () => {
-    parseBigNumber('123123123123').should.be.a('string')
-  })
-
   it('test from big number to bytes', async () => {
     // TODO investigate about float numbers serialization
     const data = [