diff --git a/src/app/api/creation/preview/route.test.ts b/src/app/api/creation/preview/route.test.ts
new file mode 100644
index 0000000..6035751
--- /dev/null
+++ b/src/app/api/creation/preview/route.test.ts
@@ -0,0 +1,50 @@
+import { GET } from './route'
+import * as creationSheets from '@/lib/creationSheets'
+import { getServerSession } from 'next-auth'
+
+jest.mock('next-auth')
+jest.mock('@/lib/creationSheets')
+jest.mock('@/lib/prisma', () => ({
+  prisma: { productCreation: { findMany: jest.fn().mockResolvedValue([]) } },
+}))
+
+const mockSession = getServerSession as jest.MockedFunction<typeof getServerSession>
+const mockFetch = creationSheets.fetchPendingProducts as jest.MockedFunction<typeof creationSheets.fetchPendingProducts>
+
+const makePending = (tab: string, row: number, specific: Record<string, string> = {}) => ({
+  tab, rowNumber: row, sku: `SKU-${row}`, title: `Produit ${row}`,
+  priceMarket: '99', priceActual: '79', stock: 5, weightKg: 2,
+  vendor: 'BOSCH', famille: tab, sousFamille: '', comment: '',
+  collectionId: '10', subCollectionId: '', hasPhoto: false,
+  specificFields: specific,
+})
+
+describe('GET /api/creation/preview', () => {
+  beforeEach(() => {
+    mockSession.mockResolvedValue({ user: { id: 'u1', role: 'admin' } } as never)
+    mockFetch.mockResolvedValue([
+      makePending('OUTILLAGE', 2, { 'Puissance (AN)': '1500W' }),
+      makePending('CARRELAGE', 3),
+    ])
+  })
+
+  it('retourne 401 sans session', async () => {
+    mockSession.mockResolvedValue(null)
+    const res = await GET(new Request('http://localhost') as never)
+    expect(res.status).toBe(401)
+  })
+
+  it('retourne les produits groupés par onglet', async () => {
+    const res = await GET(new Request('http://localhost') as never)
+    const body = await res.json()
+    expect(body.byTab['OUTILLAGE']).toHaveLength(1)
+    expect(body.byTab['CARRELAGE']).toHaveLength(1)
+    expect(body.total).toBe(2)
+  })
+
+  it('liste les colonnes spécifiques uniques', async () => {
+    const res = await GET(new Request('http://localhost') as never)
+    const body = await res.json()
+    expect(body.specificColumns).toContain('Puissance (AN)')
+  })
+})
diff --git a/src/app/api/creation/preview/route.ts b/src/app/api/creation/preview/route.ts
new file mode 100644
index 0000000..dd6746e
--- /dev/null
+++ b/src/app/api/creation/preview/route.ts
@@ -0,0 +1,28 @@
+import { NextRequest, NextResponse } from 'next/server'
+import { getServerSession } from 'next-auth'
+import { authOptions } from '@/lib/auth'
+import { fetchPendingProducts } from '@/lib/creationSheets'
+import { prisma } from '@/lib/prisma'
+import type { PendingProduct } from '@/types/creation'
+
+// eslint-disable-next-line @typescript-eslint/no-unused-vars
+export async function GET(_req: NextRequest) {
+  const session = await getServerSession(authOptions)
+  if (!session) return NextResponse.json({ error: 'Non authentifié' }, { status: 401 })
+  try {
+    const existing = await prisma.productCreation.findMany({ select: { sheetTab: true, sheetRow: true } })
+    const alreadyCreated = new Set(existing.map(e => `${e.sheetTab}:${e.sheetRow}`))
+    const pending = await fetchPendingProducts(alreadyCreated)
+    const byTab: Record<string, PendingProduct[]> = {}
+    const specificColumns = new Set<string>()
+    for (const p of pending) {
+      if (!byTab[p.tab]) byTab[p.tab] = []
+      byTab[p.tab].push(p)
+      Object.keys(p.specificFields).forEach(k => specificColumns.add(k))
+    }
+    return NextResponse.json({ byTab, total: pending.length, specificColumns: Array.from(specificColumns).sort() })
+  } catch (err) {
+    const message = err instanceof Error ? err.message : 'Erreur inconnue'
+    return NextResponse.json({ error: message }, { status: 500 })
+  }
+}