diff --git a/assets/js/form.js b/assets/js/form.js
new file mode 100644
index 0000000..a0300eb
--- /dev/null
+++ b/assets/js/form.js
@@ -0,0 +1,350 @@
+/**
+ * Umzugsliste Form JavaScript
+ *
+ * Real-time volume (cbm) calculations matching legacy logic
+ *
+ * @package Umzugsliste
+ */
+
+(function($) {
+	'use strict';
+
+	/**
+	 * Parse German decimal format to float
+	 * Converts "0,40" or "0.40" to 0.40
+	 *
+	 * @param {string|number} str Value to parse
+	 * @return {number} Parsed number or 0
+	 */
+	function parseGermanDecimal(str) {
+		if (!str || str === '') {
+			return 0;
+		}
+
+		// Convert to string and trim
+		str = String(str).trim().replace(',', '.');
+
+		// Parse as float
+		const num = parseFloat(str);
+
+		// Return 0 for invalid or negative numbers
+		return isNaN(num) || num < 0 ? 0 : num;
+	}
+
+	/**
+	 * Format number to German decimal format
+	 * Converts 0.40 to "0,40"
+	 *
+	 * @param {number} num Number to format
+	 * @param {number} decimals Number of decimal places (default 2)
+	 * @return {string} Formatted number string
+	 */
+	function formatGermanDecimal(num, decimals) {
+		decimals = decimals || 2;
+		return num.toFixed(decimals).replace('.', ',');
+	}
+
+	/**
+	 * Calculate total cbm for a single furniture item
+	 *
+	 * @param {string|number} quantity Item quantity
+	 * @param {string|number} cbm CBM value per item
+	 * @return {number} Total cbm for this item
+	 */
+	function calculateItemTotal(quantity, cbm) {
+		const qty = parseGermanDecimal(quantity);
+		const cbmVal = parseGermanDecimal(cbm);
+		return qty * cbmVal;
+	}
+
+	/**
+	 * Calculate totals for a single room
+	 *
+	 * @param {string} roomKey Room identifier (e.g., "wohnzimmer")
+	 * @return {object} Object with quantity and cbm totals
+	 */
+	function calculateRoomTotal(roomKey) {
+		let totalCbm = 0;
+		let totalQuantity = 0;
+
+		// Find all furniture rows for this room
+		$('tr[data-room="' + roomKey + '"].furniture-row').each(function() {
+			const $row = $(this);
+			const quantity = $row.find('.quantity-input').val();
+			const cbm = $row.data('cbm');
+
+			const qty = parseGermanDecimal(quantity);
+			totalQuantity += qty;
+			totalCbm += calculateItemTotal(quantity, cbm);
+		});
+
+		// Round to 2 decimal places
+		return {
+			quantity: totalQuantity,
+			cbm: Math.round(totalCbm * 100) / 100
+		};
+	}
+
+	/**
+	 * Calculate grand totals across all rooms
+	 *
+	 * @return {object} Object with quantity and cbm totals
+	 */
+	function calculateGrandTotal() {
+		let totalCbm = 0;
+		let totalQuantity = 0;
+
+		// Sum all room totals
+		$('.room-totals').each(function() {
+			const $row = $(this);
+			const roomKey = $row.closest('table').data('room');
+			const roomTotal = calculateRoomTotal(roomKey);
+
+			totalQuantity += roomTotal.quantity;
+			totalCbm += roomTotal.cbm;
+		});
+
+		// Round to 2 decimal places
+		return {
+			quantity: totalQuantity,
+			cbm: Math.round(totalCbm * 100) / 100
+		};
+	}
+
+	/**
+	 * Update display for a single room's totals
+	 *
+	 * @param {string} roomKey Room identifier
+	 */
+	function updateRoomDisplay(roomKey) {
+		const total = calculateRoomTotal(roomKey);
+		const $table = $('table[data-room="' + roomKey + '"]');
+
+		$table.find('.room-total-quantity').text(total.quantity);
+		$table.find('.room-total-cbm').text(formatGermanDecimal(total.cbm));
+	}
+
+	/**
+	 * Update grand totals display
+	 */
+	function updateGrandTotalDisplay() {
+		const total = calculateGrandTotal();
+
+		$('#grand-total-quantity').text(total.quantity);
+		$('#grand-total-cbm').text(formatGermanDecimal(total.cbm));
+	}
+
+	/**
+	 * Update all totals (rooms and grand total)
+	 */
+	function updateAllTotals() {
+		// Update each room
+		$('.room-totals').each(function() {
+			const roomKey = $(this).closest('table').data('room');
+			updateRoomDisplay(roomKey);
+		});
+
+		// Update grand total
+		updateGrandTotalDisplay();
+	}
+
+	/**
+	 * Handle quantity input change
+	 * Debounced for performance
+	 */
+	let debounceTimer;
+	function handleQuantityChange() {
+		clearTimeout(debounceTimer);
+		debounceTimer = setTimeout(function() {
+			updateAllTotals();
+		}, 100); // Quick response (100ms debounce)
+	}
+
+	/**
+	 * Validate email format
+	 *
+	 * @param {string} email Email address to validate
+	 * @return {boolean} True if valid email format
+	 */
+	function validateEmail(email) {
+		const re = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;
+		return re.test(email);
+	}
+
+	/**
+	 * Validate required field
+	 *
+	 * @param {string} value Field value
+	 * @return {boolean} True if not empty
+	 */
+	function validateRequired(value) {
+		return value && value.trim() !== '';
+	}
+
+	/**
+	 * Show error message for a field
+	 *
+	 * @param {jQuery} $field Field element
+	 * @param {string} message Error message
+	 */
+	function showFieldError($field, message) {
+		// Add error class to field
+		$field.addClass('field-error');
+
+		// Remove existing error message if any
+		clearFieldError($field);
+
+		// Add error message after field
+		$field.after('<span class="error-message">' + message + '</span>');
+	}
+
+	/**
+	 * Clear error message for a field
+	 *
+	 * @param {jQuery} $field Field element
+	 */
+	function clearFieldError($field) {
+		$field.removeClass('field-error');
+		$field.next('.error-message').remove();
+	}
+
+	/**
+	 * Validate a single field
+	 *
+	 * @param {jQuery} $field Field element
+	 * @return {boolean} True if valid
+	 */
+	function validateField($field) {
+		const fieldName = $field.attr('name');
+		const value = $field.val();
+		const isRequired = $field.attr('required') !== undefined;
+
+		// Clear existing errors
+		clearFieldError($field);
+
+		// Check required fields
+		if (isRequired && !validateRequired(value)) {
+			showFieldError($field, 'Dieses Feld ist erforderlich');
+			return false;
+		}
+
+		// Check email format
+		if (fieldName === 'info[eE-Mail]' && value) {
+			if (!validateEmail(value)) {
+				showFieldError($field, 'Bitte geben Sie eine gültige E-Mail-Adresse ein');
+				return false;
+			}
+		}
+
+		return true;
+	}
+
+	/**
+	 * Validate all furniture items - at least one must have quantity
+	 *
+	 * @return {boolean} True if valid
+	 */
+	function validateFurnitureItems() {
+		let hasItems = false;
+
+		$('.quantity-input').each(function() {
+			const qty = parseGermanDecimal($(this).val());
+			if (qty > 0) {
+				hasItems = true;
+				return false; // break loop
+			}
+		});
+
+		return hasItems;
+	}
+
+	/**
+	 * Validate date fields
+	 *
+	 * @return {boolean} True if valid date selected
+	 */
+	function validateDate() {
+		const day = $('select[name="day"]').val();
+		const month = $('select[name="month"]').val();
+		const year = $('select[name="year"]').val();
+
+		return day && month && year;
+	}
+
+	/**
+	 * Validate entire form before submission
+	 *
+	 * @return {boolean} True if all validations pass
+	 */
+	function validateForm() {
+		let isValid = true;
+		const errors = [];
+
+		// Validate date
+		if (!validateDate()) {
+			errors.push('Bitte wählen Sie ein vollständiges Umzugsdatum');
+			isValid = false;
+		}
+
+		// Validate required fields
+		$('input[required]').each(function() {
+			if (!validateField($(this))) {
+				isValid = false;
+			}
+		});
+
+		// Validate furniture items
+		if (!validateFurnitureItems()) {
+			errors.push('Bitte geben Sie mindestens ein Möbelstück ein');
+			isValid = false;
+
+			// Scroll to first room table
+			if ($('.quantity-input:first').length) {
+				$('html, body').animate({
+					scrollTop: $('.quantity-input:first').closest('table').offset().top - 100
+				}, 500);
+			}
+		}
+
+		// If there are general errors, scroll to first error field
+		if (!isValid && $('.field-error:first').length) {
+			$('html, body').animate({
+				scrollTop: $('.field-error:first').offset().top - 100
+			}, 500);
+		}
+
+		return isValid;
+	}
+
+	/**
+	 * Initialize calculations
+	 */
+	$(document).ready(function() {
+		// Attach event listeners to all quantity inputs
+		$('.quantity-input').on('input change', handleQuantityChange);
+
+		// Initial calculation (in case of pre-filled values)
+		updateAllTotals();
+
+		// Attach validation listeners
+		$('input[required], input[type="email"]').on('blur', function() {
+			validateField($(this));
+		});
+
+		// Clear error on field change
+		$('input').on('input', function() {
+			clearFieldError($(this));
+		});
+
+		// Validate form on submit
+		$('#umzugsliste-form').on('submit', function(e) {
+			if (!validateForm()) {
+				e.preventDefault();
+				return false;
+			}
+		});
+
+		console.log('Umzugsliste calculations and validation initialized');
+	});
+
+})(jQuery);