diff --git a/public/views/modals/inputAmount.html b/public/views/modals/inputAmount.html
index f2e0307e3..387a3d812 100644
--- a/public/views/modals/inputAmount.html
+++ b/public/views/modals/inputAmount.html
@@ -6,9 +6,9 @@
       </a>
     </div>
     <h1 class="title ellipsis" translate>Enter amount</h1>
-    <div class="right-small m5r" ng-show="!specificAmount" ng-click="toggleAlternative()">
-      <a class="postfix" ng-show="showAlternativeAmount">{{alternativeIsoCode}}</a>
-      <a class="postfix" ng-show="!showAlternativeAmount">{{unitName}}</a>
+    <div class="buttons m5r m3t" ng-show="!specificAmount" ng-click="toggleAlternative()">
+      <button class="button black" ng-show="showAlternativeAmount">{{alternativeIsoCode}}</button>
+      <button class="button" ng-style="{'background-color':color}" ng-show="!showAlternativeAmount">{{unitName}}</button>
     </div>
   </ion-header-bar>
 
@@ -16,8 +16,8 @@
     <div ng-show="!specificAmount">
       <div class="send-amount row" ng-style="{'background-color':index.backgroundColor}">
         <div class="size-48" ng-class="{'small-font': smallFont}">{{amount || '-'}}</div>
-        <div class="size-21 text-light" ng-show="!showAlternativeAmount">{{globalResult}} [{{amountResult || 0}} {{alternativeIsoCode}}]</div>
-        <div class="size-21 text-light" ng-show="showAlternativeAmount">{{globalResult}} [{{alternativeResult || 0}} {{unitName}}]</div>
+        <div class="size-21 text-light" ng-show="!showAlternativeAmount">{{globalResult}} [{{amountResult || '0.00'}} {{alternativeIsoCode}}]</div>
+        <div class="size-21 text-light" ng-show="showAlternativeAmount">{{globalResult}} [{{alternativeResult || '0.00'}} {{unitName}}]</div>
       </div>
 
       <div class="button-content text-center size-10 df">
diff --git a/src/js/controllers/modals/inputAmount.js b/src/js/controllers/modals/inputAmount.js
index 0be9ab6e8..77dd77726 100644
--- a/src/js/controllers/modals/inputAmount.js
+++ b/src/js/controllers/modals/inputAmount.js
@@ -1,6 +1,6 @@
 'use strict';
 
-angular.module('copayApp.controllers').controller('inputAmountController', function($rootScope, $scope, $filter, platformInfo, lodash, configService, go, rateService) {
+angular.module('copayApp.controllers').controller('inputAmountController', function($rootScope, $scope, $filter, profileService, platformInfo, lodash, configService, go, rateService) {
   var unitToSatoshi;
   var satToUnit;
   var unitDecimals;
@@ -27,9 +27,12 @@ angular.module('copayApp.controllers').controller('inputAmountController', funct
   $scope.toggleAlternative = function() {
     $scope.showAlternativeAmount = !$scope.showAlternativeAmount;
 
-    if (isExpression($scope.amount)) {
-      var decimals = $scope.showAlternativeAmount ? 2 : unitDecimals;
-      $scope.globalResult = '= ' + evaluate(format($scope.amount)).toFixed(decimals);
+    if ($scope.amount && isExpression($scope.amount)) {
+      var amount = evaluate(format($scope.amount));
+      if ($scope.showAlternativeAmount)
+        $scope.globalResult = '= ' + $filter('formatFiatAmount')(amount);
+      else
+        $scope.globalResult = '= ' + profileService.formatAmount(amount * unitToSatoshi, true);
     }
   };
 
@@ -40,9 +43,9 @@ angular.module('copayApp.controllers').controller('inputAmountController', funct
 
   $scope.pushDigit = function(digit) {
     checkFontSize();
-    if ($scope.amount && $scope.amount.length >= 20) return;
+    if ($scope.amount && $scope.amount.length >= 19) return;
 
-    $scope.amount = $scope.amount + digit;
+    $scope.amount = ($scope.amount + digit).replace('..', '.');
     processAmount($scope.amount);
   };
 
@@ -67,11 +70,11 @@ angular.module('copayApp.controllers').controller('inputAmountController', funct
   };
 
   function isExpression(val) {
-    var regex = /^\d+(\.?\d?)+$/;
+    var regex = /^\.?\d+(\.?\d+)?([\/\-\+\*x]\d?\.?\d+)+$/;
     var match = regex.exec(val);
 
-    if (match) return false;
-    return true;
+    if (match) return true;
+    return false;
   };
 
   $scope.removeDigit = function() {
@@ -100,11 +103,13 @@ angular.module('copayApp.controllers').controller('inputAmountController', funct
     var result = evaluate(formatedValue);
 
     if (lodash.isNumber(result)) {
-      var decimals = $scope.showAlternativeAmount ? 2 : unitDecimals;
+      if ($scope.showAlternativeAmount)
+        $scope.globalResult = isExpression(val) ? '= ' + $filter('formatFiatAmount')(result) : '';
+      else
+        $scope.globalResult = isExpression(val) ? '= ' + profileService.formatAmount(result * unitToSatoshi, true) : '';
 
-      $scope.globalResult = isExpression(val) ? '= ' + result.toFixed(decimals) : '';
       $scope.amountResult = $filter('formatFiatAmount')(toFiat(result));
-      $scope.alternativeResult = $filter('formatFiatAmount')(fromFiat(result));
+      $scope.alternativeResult = profileService.formatAmount(fromFiat(result) * unitToSatoshi, true);
     }
   };
 
diff --git a/src/sass/main.scss b/src/sass/main.scss
index 0ca43d701..5d6c62692 100644
--- a/src/sass/main.scss
+++ b/src/sass/main.scss
@@ -588,6 +588,10 @@ ul.manage li {
   margin-bottom: 10px;
 }
 
+.m3t {
+  margin-top: 3px;
+}
+
 .m10t {
   margin-top: 10px;
 }