diff --git a/src/main/java/pers/towdium/justEnoughCalculation/core/Calculator.java b/src/main/java/pers/towdium/justEnoughCalculation/core/Calculator.java
index 943fc76..29911e6 100644
--- a/src/main/java/pers/towdium/justEnoughCalculation/core/Calculator.java
+++ b/src/main/java/pers/towdium/justEnoughCalculation/core/Calculator.java
@@ -22,7 +22,7 @@ public class Calculator {
     public Calculator (){}
 
     public Calculator (ItemStack itemStack, int amount){
-        this(new ItemRecord(itemStack, amount), new LinkedList<OperateRecord>(), new LinkedList<ItemRecord>(), true);
+        this(new ItemRecord(itemStack, amount, false), new LinkedList<OperateRecord>(), new LinkedList<ItemRecord>(), true);
     }
 
     public Calculator (ItemRecord itemRecord, List<OperateRecord> operateRecords, List<ItemRecord> catalystBuffer, boolean exceedMode){
@@ -41,7 +41,7 @@ public class Calculator {
                 for(ItemStack itemStack : recipe.input){
                     if(itemStack != null){
                         calculatorBuilder.add(new Calculator(
-                                new ItemRecord(itemStack, count*recipe.getInputAmount(itemStack)), records, catalystBuffer, true
+                                new ItemRecord(itemStack, count*recipe.getInputAmount(itemStack), false), records, catalystBuffer, true
                         ));
                     }
                 }
@@ -77,12 +77,12 @@ public class Calculator {
         List<ItemRecord> input = new LinkedList<>();
         for(ItemStack itemStack : currentOperate.recipe.output){
             if(itemStack != null){
-                output.add(new ItemRecord(itemStack, currentOperate.count*ItemStackWrapper.getUnifiedAmount(itemStack)));
+                output.add(new ItemRecord(itemStack, currentOperate.count*ItemStackWrapper.getUnifiedAmount(itemStack), false));
             }
         }
         for(ItemStack itemStack : currentOperate.recipe.input){
             if(itemStack != null){
-                input.add(new ItemRecord(itemStack, currentOperate.count*ItemStackWrapper.getUnifiedAmount(itemStack)));
+                input.add(new ItemRecord(itemStack, currentOperate.count*ItemStackWrapper.getUnifiedAmount(itemStack), false));
             }
         }
         return new Calculator.CostRecord(output, input);
diff --git a/src/main/java/pers/towdium/justEnoughCalculation/core/ItemRecord.java b/src/main/java/pers/towdium/justEnoughCalculation/core/ItemRecord.java
index d2a5f39..85752e4 100644
--- a/src/main/java/pers/towdium/justEnoughCalculation/core/ItemRecord.java
+++ b/src/main/java/pers/towdium/justEnoughCalculation/core/ItemRecord.java
@@ -11,17 +11,20 @@ public class ItemRecord{
     Item item;
     int meta;
     long amount;
+    boolean approx;
 
-    public ItemRecord(ItemStack itemStack, long amount){
+    public ItemRecord(ItemStack itemStack, long amount, boolean approx){
         item = itemStack.getItem();
         meta = itemStack.getMetadata();
         this.amount = amount;
+        this.approx = approx;
     }
 
-    public ItemRecord(Item item, int meta, long amount) {
+    public ItemRecord(Item item, int meta, long amount, boolean approx) {
         this.item = item;
         this.meta = meta;
         this.amount = amount;
+        this.approx = approx;
     }
 
     @Override
@@ -45,6 +48,7 @@ public class ItemRecord{
     public boolean add(ItemRecord record){
         if (isSameType(record)){
             amount += record.amount;
+            approx = approx || record.approx;
             return true;
         }else {
             return false;
@@ -65,6 +69,10 @@ public class ItemRecord{
             long i = amount>record.amount ? record.amount : amount;
             amount -= i;
             record.amount -= i;
+            if(approx || record.approx){
+                approx = true;
+                record.approx = true;
+            }
             return i!=0;
         }else {
             return false;
@@ -72,14 +80,27 @@ public class ItemRecord{
     }
 
     public ItemRecord copy(){
-        return new ItemRecord(item, meta, amount);
+        return new ItemRecord(item, meta, amount, approx);
     }
 
     public ItemStack toItemStack(){
         ItemStack itemStack = new ItemStack(item, 1, meta);
         NBTTagCompound tagCompound = new NBTTagCompound();
         tagCompound.setLong("amount", amount);
+        if(approx){
+            tagCompound.setBoolean("approx", true);
+        }
         itemStack.setTagCompound(tagCompound);
         return itemStack;
     }
+
+    @Override
+    public boolean equals(Object obj) {
+        if(obj instanceof ItemRecord){
+            ItemRecord record = ((ItemRecord) obj);
+            return record.approx == approx && record.item == item && record.amount == amount && record.meta == meta;
+        }else {
+            return false;
+        }
+    }
 }
diff --git a/src/main/java/pers/towdium/justEnoughCalculation/core/ItemStackWrapper.java b/src/main/java/pers/towdium/justEnoughCalculation/core/ItemStackWrapper.java
index 0da2ace..8c4f212 100644
--- a/src/main/java/pers/towdium/justEnoughCalculation/core/ItemStackWrapper.java
+++ b/src/main/java/pers/towdium/justEnoughCalculation/core/ItemStackWrapper.java
@@ -24,10 +24,6 @@ public class ItemStackWrapper {
         }
     }
 
-    public static int getNormalAmount(ItemStack itemStack){
-        return itemStack.stackSize*100;
-    }
-
     public static String getDisplayAmount(ItemStack itemStack){
         if(itemStack != null){
             if(itemStack.getTagCompound() != null){
@@ -39,7 +35,7 @@ public class ItemStackWrapper {
                 if(i != 0){
                     return i + "%";
                 }else{
-                    return String.valueOf((l+99)/100);
+                    return getSimplifiedString((l+99)/100, itemStack.getTagCompound().getBoolean("approx"));
                 }
             }else {
                 return String.valueOf(itemStack.stackSize);
@@ -58,6 +54,7 @@ public class ItemStackWrapper {
         if(itemStack.hasTagCompound()){
             int i = itemStack.getTagCompound().getInteger("percentage");
             itemStack.stackSize = (i+99)/100;
+            itemStack.setTagCompound(null);
         }else {
             itemStack.stackSize = 1;
         }
@@ -65,6 +62,42 @@ public class ItemStackWrapper {
         return itemStack;
     }
 
+    public static String getSimplifiedString(long l, boolean approx){
+        String s;
+        if(l<999){
+            s = String.valueOf(l);
+        }else if(l<9999){
+            s = String.format("%.2fK", (double)l/1000);
+        }else if(l<99999){
+            s = String.format("%.1fK", (double)l/1000);
+        }else if(l<999999){
+            s = String.format("%.0fK", (double)l/1000);
+        }else if(l<9999999){
+            s = String.format("%.2fM", (double)l/1000000);
+        }else if(l<99999999){
+            s = String.format("%.1fM", (double)l/1000000);
+        }else if(l<999999999){
+            s = String.format("%.0fM", (double)l/1000000);
+        }else if(l<9999999999L){
+            s = String.format("%.2fB", (double)l/1000000000);
+        }else if(l<99999999999L){
+            s = String.format("%.1fB", (double)l/1000000000);
+        }else if(l<999999999999L){
+            s = String.format("%.0fB", (double)l/1000000000);
+        }else if(l<9999999999999L){
+            s = String.format("%.2fT", (double)l/1000000000000L);
+        }else if(l<99999999999999L){
+            s = String.format("%.1fT", (double)l/1000000000000L);
+        }else {
+            s = String.format("%.0fT", (double)l/1000000000000L);
+        }
+        if(approx){
+            return "≈" + s;
+        }else {
+            return s;
+        }
+    }
+
     public static class NBT {
         public static void initNBT(ItemStack itemStack){
             if(!itemStack.hasTagCompound()){
diff --git a/src/main/java/pers/towdium/justEnoughCalculation/core/Recipe.java b/src/main/java/pers/towdium/justEnoughCalculation/core/Recipe.java
index ab6f213..ceff79c 100644
--- a/src/main/java/pers/towdium/justEnoughCalculation/core/Recipe.java
+++ b/src/main/java/pers/towdium/justEnoughCalculation/core/Recipe.java
@@ -68,6 +68,28 @@ public class Recipe {
         return -1;
     }
 
+    public int getExactInputIndex(ItemStack itemStack){
+        for(int i = 0; i<12; i++){
+            if(ItemStackWrapper.isStackEqual(input[i], itemStack)){
+                return i;
+            }
+        }
+        return -1;
+    }
+
+    public int getInputIndex(ItemStack itemStack){
+        for(int i = 0; i<12; i++){
+            if(ItemStackWrapper.isTypeEqual(input[i], itemStack)){
+                return i;
+            }
+        }
+        return -1;
+    }
+
+    public boolean getHasExactInput(ItemStack itemStack){
+        return getExactInputIndex(itemStack) != -1;
+    }
+
     public int getOutputAmount(ItemStack itemStack){
         for(int i = 0; i<4; i++){
             if(ItemStackWrapper.isTypeEqual(output[i], itemStack)){
@@ -90,6 +112,10 @@ public class Recipe {
         return getOutputIndex(itemStack) != -1;
     }
 
+    public boolean getHasInput(ItemStack itemStack){
+        return getInputIndex(itemStack) != -1;
+    }
+
     @Override
     public boolean equals(Object obj) {
         if(obj instanceof Recipe){
@@ -138,6 +164,20 @@ public class Recipe {
         return builder.build();
     }
 
+    public boolean isApprox(){
+        for(ItemStack itemstack : input){
+            if(itemstack != null && itemstack.hasTagCompound() && itemstack.getTagCompound().hasKey("percentage")){
+                return true;
+            }
+        }
+        for(ItemStack itemstack : output){
+            if(itemstack != null && itemstack.hasTagCompound() && itemstack.getTagCompound().hasKey("percentage")){
+                return true;
+            }
+        }
+        return false;
+    }
+
     public static class ByteBufUtl{
         public static Recipe fromByte(ByteBuf buf){
             short a = buf.readShort();
diff --git a/src/main/java/pers/towdium/justEnoughCalculation/gui/guis/calculator/GuiCalculator.java b/src/main/java/pers/towdium/justEnoughCalculation/gui/guis/calculator/GuiCalculator.java
index cccc1e0..e4a088b 100644
--- a/src/main/java/pers/towdium/justEnoughCalculation/gui/guis/calculator/GuiCalculator.java
+++ b/src/main/java/pers/towdium/justEnoughCalculation/gui/guis/calculator/GuiCalculator.java
@@ -266,7 +266,7 @@ public class GuiCalculator extends GuiTooltipScreen{
             Calculator.CostRecord record = calculator.getCost();
             record.unify();
             costRecord = record;
-        } catch (Exception e){
+        } catch (NumberFormatException e){
             textFieldAmount.setTextColor(16711680);
             TimerTask r = new TimerTask() {
                 @Override