diff --git a/src/app/api/sync/preview/route.ts b/src/app/api/sync/preview/route.ts
index f0a42d5..f84b321 100644
--- a/src/app/api/sync/preview/route.ts
+++ b/src/app/api/sync/preview/route.ts
@@ -11,7 +11,7 @@ export async function GET(req: NextRequest) {
       fetchAllShopifyProducts(),
     ])
 
-    const diff = computeDiff(sheetProducts, shopifyProducts)
+    const diff = computeDiff(sheetProducts, shopifyProducts, tab)
     return NextResponse.json(diff)
   } catch (err) {
     const message = err instanceof Error ? err.message : 'Erreur inconnue'
diff --git a/src/lib/syncDiff.ts b/src/lib/syncDiff.ts
index f13f423..8036da7 100644
--- a/src/lib/syncDiff.ts
+++ b/src/lib/syncDiff.ts
@@ -18,10 +18,13 @@ function getChangedFields(
 /**
  * Calcule le diff entre les produits Sheets et Shopify.
  * Matching par handle (ref normalisée).
+ * Si tabFilter est fourni, les désactivations sont ignorées : on ne peut pas savoir
+ * si un produit Shopify absent du tab appartient à une autre famille ou a été supprimé.
  */
 export function computeDiff(
   sheetProducts: SyncProduct[],
   shopifyProducts: ShopifyProductFull[],
+  tabFilter?: string,
 ): DiffResult {
   const shopifyMap = new Map(shopifyProducts.map((p) => [p.handle, p]))
   const sheetHandles = new Set(sheetProducts.map((p) => p.handle))
@@ -48,9 +51,12 @@ export function computeDiff(
     }
   }
 
-  for (const shopify of shopifyProducts) {
-    if (shopify.status === 'active' && !sheetHandles.has(shopify.handle)) {
-      changes.push({ type: 'deactivate', ref: shopify.ref, shopifyProduct: shopify })
+  // Désactivations uniquement en mode catalogue complet (sans filtre par famille)
+  if (!tabFilter) {
+    for (const shopify of shopifyProducts) {
+      if (shopify.status === 'active' && !sheetHandles.has(shopify.handle)) {
+        changes.push({ type: 'deactivate', ref: shopify.ref, shopifyProduct: shopify })
+      }
     }
   }