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diff --git a/ui/app/conversion-util.js b/ui/app/conversion-util.js
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+/* Currency Conversion Utility
+* This utility function can be used for converting currency related values within metamask.
+* The caller should be able to pass it a value, along with information about the value's
+* numeric base, denomination and currency, and the desired numeric base, denomination and
+* currency. It should return a single value.
+*
+* @param {(number | string | BN)} value The value to convert.
+* @param {Object} [options] Options to specify details of the conversion
+* @param {string} [options.fromCurrency = 'ETH' | 'USD'] The currency of the passed value
+* @param {string} [options.toCurrency = 'ETH' | 'USD'] The desired currency of the result
+* @param {string} [options.fromNumericBase = 'hex' | 'dec' | 'BN'] The numeric basic of the passed value.
+* @param {string} [options.toNumericBase = 'hex' | 'dec' | 'BN'] The desired numeric basic of the result.
+* @param {string} [options.fromDenomination = 'WEI'] The denomination of the passed value
+* @param {number} [options.numberOfDecimals] The desired number of in the result
+* @param {number} [options.conversionRate] The rate to use to make the fromCurrency -> toCurrency conversion
+* @param {number} [options.ethToUSDRate] If present, a second conversion - at ethToUSDRate - happens after conversionRate is applied.
+* @returns {(number | string | BN)}
+*
+* The utility passes value along with the options as a single object to the `converter` function.
+* `converter` uses Ramda.js to apply a composition of conditional setters to the `value` property, depending
+* on the accompanying options. Some of these conditional setters are selected via key-value maps, where
+* the keys are specified in the options parameters and the values are setter functions.
+*/
+
+const BigNumber = require('bignumber.js')
+const R = require('ramda')
+const { stripHexPrefix } = require('ethereumjs-util')
+
+BigNumber.config({
+  ROUNDING_MODE: BigNumber.ROUND_HALF_DOWN,
+})
+
+// Big Number Constants
+const BIG_NUMBER_WEI_MULTIPLIER = new BigNumber('1000000000000000000')
+
+// Individual Setters
+const convert = R.invoker(1, 'times')
+const round = R.invoker(2, 'toFormat')(R.__, BigNumber.ROUND_DOWN)
+
+// Setter Maps
+const toBigNumber = {
+  hex: n => new BigNumber(stripHexPrefix(n), 16),
+  dec: n => new BigNumber(n, 10),
+  BN: n => new BigNumber(n.toString(16), 16),
+}
+const toNormalizedDenomination = {
+  WEI: bigNumber => bigNumber.div(BIG_NUMBER_WEI_MULTIPLIER)
+}
+const toSpecifiedDenomination = {
+  WEI: bigNumber => bigNumber.times(BIG_NUMBER_WEI_MULTIPLIER)
+}
+const baseChange = {
+  hex: n => n.toString(16),
+  dec: n => n.toString(10),
+  BN: n => new BN(n.toString(16)),
+}
+
+// Predicates
+const fromAndToCurrencyPropsNotEqual = R.compose(
+  R.not,
+  R.eqBy(R.__, 'fromCurrency', 'toCurrency'),
+  R.flip(R.prop)
+)
+
+// Lens
+const valuePropertyLense = R.over(R.lensProp('value'))
+
+// conditional 'value' setting wrappers
+const whenPredSetWithPropAndSetter = (pred, prop, setter) => R.when(
+  pred,
+  R.converge(
+    valuePropertyLense,
+    [R.pipe(R.prop(prop), setter), R.identity]
+  )
+)
+const whenPropApplySetterMap = (prop, setterMap) => whenPredSetWithPropAndSetter(
+  R.prop(prop),
+  prop,
+  R.prop(R.__, setterMap)
+)
+
+// Conversion utility function
+const converter = R.pipe(
+  whenPropApplySetterMap('fromNumericBase', toBigNumber),
+  whenPropApplySetterMap('fromDenomination', toNormalizedDenomination),
+  whenPropApplySetterMap('toDenomination', toSpecifiedDenomination),
+  whenPredSetWithPropAndSetter(fromAndToCurrencyPropsNotEqual, 'conversionRate', convert),
+  whenPredSetWithPropAndSetter(R.prop('ethToUSDRate'), 'ethToUSDRate', convert),
+  whenPredSetWithPropAndSetter(R.prop('numberOfDecimals'), 'numberOfDecimals', round),
+  whenPropApplySetterMap('toNumericBase', baseChange),
+  R.view(R.lensProp('value'))
+);
+
+const conversionUtil = (value, {
+  fromCurrency = null,
+  toCurrency = fromCurrency,
+  fromNumericBase,
+  toNumericBase,
+  fromDenomination,
+  toDenomination,
+  numberOfDecimals,
+  conversionRate,
+  ethToUSDRate,
+}) => converter({
+  fromCurrency,
+  toCurrency,
+  fromNumericBase,
+  toNumericBase,
+  fromDenomination,
+  toDenomination,
+  numberOfDecimals,
+  conversionRate,
+  ethToUSDRate,
+  value,
+});
+
+module.exports = {
+  conversionUtil,
+}
+\ No newline at end of file