diff --git a/hdyc-svelte/src/lib/components/Calculator.svelte b/hdyc-svelte/src/lib/components/Calculator.svelte
index e2f4bf6..3438bfa 100644
--- a/hdyc-svelte/src/lib/components/Calculator.svelte
+++ b/hdyc-svelte/src/lib/components/Calculator.svelte
@@ -26,17 +26,21 @@
   let footerControlsEl: HTMLDivElement | null = null;
   let tooltipX = 20;
   let copyStatusMessage = '';
+  let initializedSlug: string | null = null;
 
   $: has3 = ['3col', '3col-mul'].includes(config.type) || !!config.labels.in3;
   $: isTextInput = ['base', 'text-bin', 'bin-text', 'dec-frac', 'dms-dd', 'dd-dms'].includes(config.type);
 
-  // Clear inputs on config (route) change
-  $: if (config) {
-    if (!paramsInitializing) clear();
+  // Clear inputs only when navigating to a different calculator slug.
+  $: if (config?.slug) {
+    if (initializedSlug === null) {
+      initializedSlug = config.slug;
+    } else if (initializedSlug !== config.slug) {
+      initializedSlug = config.slug;
+      clear();
+    }
   }
 
-  let paramsInitializing = true;
-
   function handleInput(source: 1 | 2 | 3, options?: { preserveSwap?: boolean }) {
     if (!options?.preserveSwap) {
       swapState = null;
@@ -81,7 +85,6 @@
     const v2 = toQueryValue(val2);
     const v3 = toQueryValue(val3);
     const source: 1 | 2 | 3 = has3 ? activeField : (activeField === 2 ? 2 : 1);
-    params.set('src', String(source));
 
     if (!has3) {
       const sourceValue = source === 1 ? v1 : v2;
@@ -189,26 +192,28 @@
 
   onMount(() => {
     const params = new URLSearchParams($page.url.search);
-    const srcParam = Number(params.get('src'));
-    const shareSource = srcParam === 1 || srcParam === 2 || srcParam === 3 ? srcParam : null;
+    const hasV1 = params.has('v1');
+    const hasV2 = params.has('v2');
+    const hasV3 = has3 && params.has('v3');
 
-    if (shareSource !== null) {
-      if (params.has('v1')) val1 = params.get('v1') ?? '';
-      if (params.has('v2')) val2 = params.get('v2') ?? '';
-      if (params.has('v3') && has3) val3 = params.get('v3') ?? '';
-      const sourceToApply: 1 | 2 | 3 = has3 ? shareSource : (shareSource === 2 ? 2 : 1);
-      handleInput(sourceToApply);
-    } else if (params.has('v1')) {
+    if (has3 && hasV2 && hasV3) {
+      val2 = params.get('v2') ?? '';
+      val3 = params.get('v3') ?? '';
+      handleInput(3);
+    } else if (has3 && hasV1 && hasV2) {
+      val1 = params.get('v1') ?? '';
+      val2 = params.get('v2') ?? '';
+      handleInput(1);
+    } else if (hasV1) {
       val1 = params.get('v1') ?? '';
       handleInput(1);
-    } else if (params.has('v2')) {
+    } else if (hasV2) {
       val2 = params.get('v2') ?? '';
       handleInput(2);
-    } else if (params.has('v3') && has3) {
+    } else if (hasV3) {
       val3 = params.get('v3') ?? '';
       handleInput(3);
     }
-    setTimeout(() => { paramsInitializing = false; }, 0);
   });
 
   onDestroy(() => {