1 files changed, 18 insertions, 2 deletions
diff --git a/ui/app/conversion-util.js b/ui/app/conversion-util.js
index 9359d7c90..ee42ebea1 100644
--- a/ui/app/conversion-util.js
+++ b/ui/app/conversion-util.js
@@ -37,7 +37,7 @@ const BIG_NUMBER_GWEI_MULTIPLIER = new BigNumber('1000000000')
 
 // Individual Setters
 const convert = R.invoker(1, 'times')
-const round = R.invoker(2, 'round')(R.__, BigNumber.ROUND_DOWN)
+const round = R.invoker(2, 'round')(R.__, BigNumber.ROUND_HALF_DOWN)
 const invertConversionRate = conversionRate => () => new BigNumber(1.0).div(conversionRate)
 const decToBigNumberViaString = n => R.pipe(String, toBigNumber['dec'])
 
@@ -53,7 +53,7 @@ const toNormalizedDenomination = {
 }
 const toSpecifiedDenomination = {
   WEI: bigNumber => bigNumber.times(BIG_NUMBER_WEI_MULTIPLIER).round(),
-  GWEI: bigNumber => bigNumber.times(BIG_NUMBER_GWEI_MULTIPLIER).round(1),
+  GWEI: bigNumber => bigNumber.times(BIG_NUMBER_GWEI_MULTIPLIER).round(9),
 }
 const baseChange = {
   hex: n => n.toString(16),
@@ -145,6 +145,20 @@ const addCurrencies = (a, b, options = {}) => {
   })
 }
 
+const subtractCurrencies = (a, b, options = {}) => {
+  const {
+    aBase,
+    bBase,
+    ...conversionOptions
+  } = options
+  const value = (new BigNumber(a, aBase)).minus(b, bBase)
+
+  return converter({
+    value,
+    ...conversionOptions,
+  })
+}
+
 const multiplyCurrencies = (a, b, options = {}) => {
   const {
     multiplicandBase,
@@ -169,6 +183,7 @@ const conversionGreaterThan = (
 ) => {
   const firstValue = converter({ ...firstProps })
   const secondValue = converter({ ...secondProps })
+
   return firstValue.gt(secondValue)
 }
 
@@ -202,4 +217,5 @@ module.exports = {
   conversionGTE,
   conversionLTE,
   toNegative,
+  subtractCurrencies,
 }