diff --git a/src/main/java/appeng/client/gui/MathExpressionParser.java b/src/main/java/appeng/client/gui/MathExpressionParser.java
new file mode 100644
index 000000000..dc1696fc0
--- /dev/null
+++ b/src/main/java/appeng/client/gui/MathExpressionParser.java
@@ -0,0 +1,208 @@
+package appeng.client.gui;
+
+import java.math.BigDecimal;
+import java.math.RoundingMode;
+import java.util.Collections;
+import java.util.Stack;
+
+public class MathExpressionParser {
+
+    private final Stack<String> postfixStack = new Stack<>();
+    private final Stack<Character> opStack = new Stack<>();
+    private static final int[] OPERATOR_PRIORITY = new int[] { 0, 3, 2, 1, -1, 1, 0, 2 };
+
+    public static double parse(String expression) {
+        double result;
+
+        if (expression == null) return Double.NaN;
+
+        expression = expression.replace(" ", "");
+
+        if (expression.length() == 1 && Character.isDigit(expression.charAt(0))) {
+            return expression.charAt(0) - '0';
+        }
+        try {
+            expression = transform(expression);
+            result = new MathExpressionParser().calculate(expression);
+        } catch (Exception e) {
+            return Double.NaN;
+        }
+        return result;
+    }
+
+    /**
+     * replace '-' with '~'
+     * e.g.-2+-1*(-3E-2)-(-1) -> ~2+~1*(~3E~2)-(~1)
+     */
+    private static String transform(String expression) {
+        char[] arr = expression.toCharArray();
+        for (int i = 0; i < arr.length; i++) {
+            if (arr[i] == '-') {
+                if (i == 0) {
+                    arr[i] = '~';
+                } else {
+                    char c = arr[i - 1];
+                    if (c == '+' || c == '-' || c == '*' || c == '/' || c == '(' || c == 'E' || c == 'e') {
+                        arr[i] = '~';
+                    }
+                }
+            }
+        }
+        if (arr[0] == '~' || arr[1] == '(') {
+            arr[0] = '-';
+            return "0" + new String(arr);
+        } else {
+            return new String(arr);
+        }
+    }
+
+    public double calculate(String expression) {
+        Stack<String> resultStack = new Stack<>();
+        prepare(expression);
+        Collections.reverse(postfixStack);
+        String firstValue, secondValue, currentValue;
+        while (!postfixStack.isEmpty()) {
+            currentValue = postfixStack.pop();
+            if (!isOperator(currentValue.charAt(0))) {
+                currentValue = currentValue.replace("~", "-");
+                resultStack.push(currentValue);
+            } else {
+                secondValue = resultStack.pop();
+                firstValue = resultStack.pop();
+
+                firstValue = firstValue.replace("~", "-");
+                secondValue = secondValue.replace("~", "-");
+
+                String tempResult = calculate(firstValue, secondValue, currentValue.charAt(0));
+                resultStack.push(String.valueOf(tempResult));
+            }
+        }
+        return Double.parseDouble(resultStack.pop());
+    }
+
+    private void prepare(String expression) {
+        opStack.push(',');
+        char[] arr = expression.toCharArray();
+        int currentIndex = 0;
+        int count = 0;
+        char currentOp, peekOp;
+        for (int i = 0; i < arr.length; i++) {
+            currentOp = arr[i];
+            if (isOperator(currentOp)) {
+                if (count > 0) {
+                    postfixStack.push(new String(arr, currentIndex, count));
+                }
+                peekOp = opStack.peek();
+                if (currentOp == ')') {
+                    while (opStack.peek() != '(') {
+                        postfixStack.push(String.valueOf(opStack.pop()));
+                    }
+                    opStack.pop();
+                } else {
+                    while (currentOp != '(' && peekOp != ',' && compare(currentOp, peekOp)) {
+                        postfixStack.push(String.valueOf(opStack.pop()));
+                        peekOp = opStack.peek();
+                    }
+                    opStack.push(currentOp);
+                }
+                count = 0;
+                currentIndex = i + 1;
+            } else {
+                count++;
+            }
+        }
+        if (count > 1 || (count == 1 && !isOperator(arr[currentIndex]))) {
+            postfixStack.push(new String(arr, currentIndex, count));
+        }
+
+        while (opStack.peek() != ',') {
+            postfixStack.push(String.valueOf(opStack.pop()));
+        }
+    }
+
+    private static boolean isOperator(char c) {
+        return c == '+' || c == '-' || c == '*' || c == '/' || c == '(' || c == ')';
+    }
+
+    private static boolean compare(char cur, char peek) {
+        return OPERATOR_PRIORITY[(peek) - 40] >= OPERATOR_PRIORITY[(cur) - 40];
+    }
+
+    private String calculate(String firstValue, String secondValue, char currentOp) {
+        return switch (currentOp) {
+            case '+' -> add(firstValue, secondValue);
+            case '-' -> sub(firstValue, secondValue);
+            case '*' -> mul(firstValue, secondValue);
+            case '/' -> div(firstValue, secondValue);
+            default -> "";
+        };
+    }
+
+    public static String add(String v1, String v2) {
+        BigDecimal b1 = new BigDecimal(v1);
+        BigDecimal b2 = new BigDecimal(v2);
+        return String.valueOf(b1.add(b2));
+    }
+
+    /**
+     * subtraction
+     *
+     * @param v1 p1
+     * @param v2 p2
+     * @return sub
+     */
+    public static String sub(String v1, String v2) {
+        BigDecimal b1 = new BigDecimal(v1);
+        BigDecimal b2 = new BigDecimal(v2);
+        return String.valueOf(b1.subtract(b2));
+    }
+
+    /**
+     * multiplication
+     *
+     * @param v1 p1
+     * @param v2 p2
+     * @return mul
+     */
+    public static String mul(String v1, String v2) {
+        BigDecimal b1 = new BigDecimal(v1);
+        BigDecimal b2 = new BigDecimal(v2);
+        return String.valueOf(b1.multiply(b2));
+    }
+
+    /**
+     * division. e = 10^-10
+     *
+     * @param v1 p1
+     * @param v2 p2
+     * @return div
+     */
+    public static String div(String v1, String v2) {
+        BigDecimal b1 = new BigDecimal(v1);
+        BigDecimal b2 = new BigDecimal(v2);
+        return String.valueOf(b1.divide(b2, 16, RoundingMode.HALF_UP));
+    }
+
+    /**
+     * rounding
+     *
+     * @param v     p
+     * @param scale scale
+     * @return result
+     */
+    public static double round(double v, int scale) {
+        if (scale < 0) {
+            throw new IllegalArgumentException("The scale must be a positive integer or zero");
+        }
+        BigDecimal b = new BigDecimal(Double.toString(v));
+        return b.divide(BigDecimal.ONE, scale, RoundingMode.HALF_UP).doubleValue();
+    }
+
+    public static String round(String v, int scale) {
+        if (scale < 0) {
+            throw new IllegalArgumentException("The scale must be a positive integer or zero");
+        }
+        BigDecimal b = new BigDecimal(v);
+        return String.valueOf(b.divide(BigDecimal.ONE, scale, RoundingMode.HALF_UP));
+    }
+}
diff --git a/src/main/java/appeng/client/gui/implementations/GuiCraftAmount.java b/src/main/java/appeng/client/gui/implementations/GuiCraftAmount.java
index 02e07e2a8..8a2935b94 100644
--- a/src/main/java/appeng/client/gui/implementations/GuiCraftAmount.java
+++ b/src/main/java/appeng/client/gui/implementations/GuiCraftAmount.java
@@ -22,10 +22,9 @@ package appeng.client.gui.implementations;
 import appeng.api.AEApi;
 import appeng.api.definitions.IDefinitions;
 import appeng.api.definitions.IParts;
-import appeng.api.features.IWirelessTermHandler;
 import appeng.api.storage.ITerminalHost;
 import appeng.client.gui.AEBaseGui;
-import appeng.client.gui.widgets.GuiNumberBox;
+import appeng.client.gui.MathExpressionParser;
 import appeng.client.gui.widgets.GuiTabButton;
 import appeng.container.AEBaseContainer;
 import appeng.container.implementations.ContainerCraftAmount;
@@ -42,6 +41,7 @@ import appeng.parts.reporting.PartExpandedProcessingPatternTerminal;
 import appeng.parts.reporting.PartPatternTerminal;
 import appeng.parts.reporting.PartTerminal;
 import net.minecraft.client.gui.GuiButton;
+import net.minecraft.client.gui.GuiTextField;
 import net.minecraft.entity.player.InventoryPlayer;
 import net.minecraft.item.ItemStack;
 import org.lwjgl.input.Keyboard;
@@ -50,7 +50,7 @@ import java.io.IOException;
 
 
 public class GuiCraftAmount extends AEBaseGui {
-    private GuiNumberBox amountToCraft;
+    private GuiTextField amountToCraft;
     private GuiTabButton originalGuiBtn;
 
     private GuiButton next;
@@ -126,7 +126,7 @@ public class GuiCraftAmount extends AEBaseGui {
             this.buttonList.add(this.originalGuiBtn = new GuiTabButton(this.guiLeft + 154, this.guiTop, myIcon, myIcon.getDisplayName(), this.itemRender));
         }
 
-        this.amountToCraft = new GuiNumberBox(this.fontRenderer, this.guiLeft + 62, this.guiTop + 57, 59, this.fontRenderer.FONT_HEIGHT, Integer.class);
+        this.amountToCraft = new GuiTextField(0, this.fontRenderer, this.guiLeft + 62, this.guiTop + 57, 59, this.fontRenderer.FONT_HEIGHT);
         this.amountToCraft.setEnableBackgroundDrawing(false);
         this.amountToCraft.setMaxStringLength(16);
         this.amountToCraft.setTextColor(0xFFFFFF);
@@ -149,8 +149,17 @@ public class GuiCraftAmount extends AEBaseGui {
         this.drawTexturedModalRect(offsetX, offsetY, 0, 0, this.xSize, this.ySize);
 
         try {
-            long amt = Long.parseLong(this.amountToCraft.getText());
-            this.next.enabled = (!this.amountToCraft.getText().isEmpty() && amt > 0);
+            String out = this.amountToCraft.getText();
+            double resultD = MathExpressionParser.parse(out);
+            long amt;
+
+            if (resultD <= 0 || Double.isNaN(resultD)) {
+                amt = 0;
+            } else {
+                amt = (long) MathExpressionParser.round(resultD, 0);
+            }
+
+            this.next.enabled = amt > 0;
         } catch (final NumberFormatException e) {
             this.next.enabled = false;
         }
@@ -164,33 +173,7 @@ public class GuiCraftAmount extends AEBaseGui {
             if (key == Keyboard.KEY_RETURN || key == Keyboard.KEY_NUMPADENTER) {
                 this.actionPerformed(this.next);
             }
-            if ((key == 211 || key == 205 || key == 203 || key == 14 || character == '-' || Character.isDigit(character)) && this.amountToCraft
-                    .textboxKeyTyped(character, key)) {
-                try {
-                    String out = this.amountToCraft.getText();
-
-                    boolean fixed = false;
-                    while (out.startsWith("0") && out.length() > 1) {
-                        out = out.substring(1);
-                        fixed = true;
-                    }
-
-                    if (fixed) {
-                        this.amountToCraft.setText(out);
-                    }
-
-                    if (out.isEmpty()) {
-                        out = "0";
-                    }
-
-                    final long result = Long.parseLong(out);
-                    if (result < 0) {
-                        this.amountToCraft.setText("1");
-                    }
-                } catch (final NumberFormatException e) {
-                    // :P
-                }
-            } else {
+            if (!this.amountToCraft.textboxKeyTyped(character, key)) {
                 super.keyTyped(character, key);
             }
         }
@@ -207,7 +190,15 @@ public class GuiCraftAmount extends AEBaseGui {
             }
 
             if (btn == this.next) {
-                NetworkHandler.instance().sendToServer(new PacketCraftRequest(Integer.parseInt(this.amountToCraft.getText()), isShiftKeyDown()));
+                double resultD = MathExpressionParser.parse(this.amountToCraft.getText());
+                int result;
+                if (resultD <= 0 || Double.isNaN(resultD)) {
+                    result = 1;
+                } else {
+                    result = (int) MathExpressionParser.round(resultD, 0);
+                }
+
+                NetworkHandler.instance().sendToServer(new PacketCraftRequest(result, isShiftKeyDown()));
             }
         } catch (final NumberFormatException e) {
             // nope..
@@ -226,22 +217,15 @@ public class GuiCraftAmount extends AEBaseGui {
         try {
             String out = this.amountToCraft.getText();
 
-            boolean fixed = false;
-            while (out.startsWith("0") && out.length() > 1) {
-                out = out.substring(1);
-                fixed = true;
-            }
+            double resultD = MathExpressionParser.parse(out);
+            int result;
 
-            if (fixed) {
-                this.amountToCraft.setText(out);
+            if (resultD <= 0 || Double.isNaN(resultD)) {
+                result = 0;
+            } else {
+                result = (int) MathExpressionParser.round(resultD, 0);
             }
 
-            if (out.isEmpty()) {
-                out = "0";
-            }
-
-            long result = Integer.parseInt(out);
-
             if (result == 1 && i > 1) {
                 result = 0;
             }
@@ -251,8 +235,7 @@ public class GuiCraftAmount extends AEBaseGui {
                 result = 1;
             }
 
-            out = Long.toString(result);
-            Integer.parseInt(out);
+            out = Integer.toString(result);
             this.amountToCraft.setText(out);
         } catch (final NumberFormatException e) {
             // :P
diff --git a/src/test/java/appeng/client/gui/MathExpressionParserTest.java b/src/test/java/appeng/client/gui/MathExpressionParserTest.java
new file mode 100644
index 000000000..eef0776ea
--- /dev/null
+++ b/src/test/java/appeng/client/gui/MathExpressionParserTest.java
@@ -0,0 +1,55 @@
+package appeng.client.gui;
+
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.CsvSource;
+
+import java.text.DecimalFormat;
+import java.text.DecimalFormatSymbols;
+import java.util.Locale;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class MathExpressionParserTest {
+
+    @ParameterizedTest
+    @CsvSource(value = {
+            "1 + 2|3",
+            "3 *4 |12",
+            "1 + 2 * 3 |7",
+            "1 - 6|-5",
+            "1/3|0.333333",
+            "23.4 + 0.6|24",
+            "1 - -4|5",
+            "1 + 4*3*2|25",
+            "1/0|failed",
+            "1/(1 - 1)|failed",
+            "3 + 2 * 4 - 1 /2|10.5",
+            "1 + (2 * (2 * (1 + 1)))|9",
+            "arkazkdhz|failed",
+            "1 + 2 3 7 - 1|237", // whitespace is trimmed
+            "2 + + 2|failed",
+            "10e6|10000000",
+            "-1 -1|-2",
+            "- (1 + 1)|-2",
+            "2 * -1|-2",
+            "2 -2|0",
+            "-  1|-1",
+            "-1|-1",
+            "- - - - - 5|failed", // not able to handle multiple negations, may fix in the future
+            "-(-(-(-2)))|failed", // not able to handle multiple negations, may fix in the future
+            "1 - -1|2",
+            "1 + -(2|failed"
+    }, delimiter = '|')
+    void testMath(String expression, String expected) {
+        DecimalFormat format = new DecimalFormat("#.######", DecimalFormatSymbols.getInstance(Locale.US));
+        format.setParseBigDecimal(true);
+        format.setNegativePrefix("-");
+
+        double parsed = MathExpressionParser.parse(expression);
+        if (Double.isNaN(parsed)) {
+            assertEquals(expected, "failed");
+        } else {
+            assertEquals(expected, format.format(parsed));
+        }
+    }
+}