diff --git a/src-ui/src/app/app-routing.module.ts b/src-ui/src/app/app-routing.module.ts
index 993ba32d1..28831a424 100644
--- a/src-ui/src/app/app-routing.module.ts
+++ b/src-ui/src/app/app-routing.module.ts
@@ -292,6 +292,7 @@ export const routes: Routes = [
       {
         path: 'ocr-templates/new',
         component: OcrTemplateEditorComponent,
+        canDeactivate: [DirtyFormGuard],
         canActivate: [PermissionsGuard],
         data: {
           requiredPermission: {
@@ -304,6 +305,7 @@ export const routes: Routes = [
       {
         path: 'ocr-templates/:id',
         component: OcrTemplateEditorComponent,
+        canDeactivate: [DirtyFormGuard],
         canActivate: [PermissionsGuard],
         data: {
           requiredPermission: {
diff --git a/src-ui/src/app/components/manage/ocr-templates/ocr-template-editor/ocr-template-editor.component.html b/src-ui/src/app/components/manage/ocr-templates/ocr-template-editor/ocr-template-editor.component.html
index 016a41f14..6c6f310d9 100644
--- a/src-ui/src/app/components/manage/ocr-templates/ocr-template-editor/ocr-template-editor.component.html
+++ b/src-ui/src/app/components/manage/ocr-templates/ocr-template-editor/ocr-template-editor.component.html
@@ -2,7 +2,7 @@
   <a routerLink="/ocr-templates" class="btn btn-sm btn-outline-secondary" title="Close" i18n-title aria-label="Close" i18n-aria-label>
     <i-bs width="1.2em" height="1.2em" name="x"></i-bs><span class="d-none d-lg-inline ps-1" i18n>Close</span>
   </a>
-  <button type="button" class="btn btn-sm btn-primary" (click)="save()" [disabled]="saving">
+  <button type="button" class="btn btn-sm btn-primary" (click)="save()" [disabled]="saving || !isDirty">
     @if (saving) {
       <span class="spinner-border spinner-border-sm me-1" aria-hidden="true"></span>
     }
diff --git a/src-ui/src/app/components/manage/ocr-templates/ocr-template-editor/ocr-template-editor.component.spec.ts b/src-ui/src/app/components/manage/ocr-templates/ocr-template-editor/ocr-template-editor.component.spec.ts
index 027b08de8..bf7da2a82 100644
--- a/src-ui/src/app/components/manage/ocr-templates/ocr-template-editor/ocr-template-editor.component.spec.ts
+++ b/src-ui/src/app/components/manage/ocr-templates/ocr-template-editor/ocr-template-editor.component.spec.ts
@@ -301,6 +301,24 @@ describe('OcrTemplateEditorComponent', () => {
     })
   })
 
+  it('tracks unsaved changes against the last loaded or saved state', () => {
+    fixture.detectChanges()
+    expect(component.isDirty$()).toBe(false)
+
+    component.template.combine_formats = { '1': '' }
+    expect(component.isDirty).toBe(false)
+
+    component.template.name = 'Invoices'
+    expect(component.isDirty).toBe(true)
+
+    templates.create.mockReturnValue(of({ ...component.template, id: 3 }))
+    component.save()
+    expect(component.isDirty).toBe(false)
+
+    component.previewDocId = 5
+    expect(component.isDirty).toBe(true)
+  })
+
   it('hides results when extraction settings or geometry change', () => {
     const selected = zone()
     component.template.zones = [selected]
diff --git a/src-ui/src/app/components/manage/ocr-templates/ocr-template-editor/ocr-template-editor.component.ts b/src-ui/src/app/components/manage/ocr-templates/ocr-template-editor/ocr-template-editor.component.ts
index a611b643f..ba70a0e50 100644
--- a/src-ui/src/app/components/manage/ocr-templates/ocr-template-editor/ocr-template-editor.component.ts
+++ b/src-ui/src/app/components/manage/ocr-templates/ocr-template-editor/ocr-template-editor.component.ts
@@ -19,6 +19,7 @@ import {
   NgbTypeaheadModule,
   NgbTypeaheadSelectItemEvent,
 } from '@ng-bootstrap/ng-bootstrap'
+import { DirtyComponent } from '@ngneat/dirty-check-forms'
 import { NgxBootstrapIconsModule } from 'ngx-bootstrap-icons'
 import {
   catchError,
@@ -142,7 +143,9 @@ const RESIZE_CURSOR: Record<ResizeHandle, string> = {
   templateUrl: './ocr-template-editor.component.html',
   styleUrls: ['./ocr-template-editor.component.scss'],
 })
-export class OcrTemplateEditorComponent implements OnInit, OnDestroy {
+export class OcrTemplateEditorComponent
+  implements OnInit, OnDestroy, DirtyComponent
+{
   private readonly route = inject(ActivatedRoute)
   private readonly templateService = inject(OcrTemplateService)
   private readonly customFieldsService = inject(CustomFieldsService)
@@ -269,6 +272,30 @@ export class OcrTemplateEditorComponent implements OnInit, OnDestroy {
       : null
   }
 
+  /** Snapshot of the editor state as last loaded or saved. */
+  private savedState = ''
+
+  get isDirty(): boolean {
+    return this.editorState() !== this.savedState
+  }
+
+  readonly isDirty$ = () => this.isDirty
+
+  private editorState(): string {
+    const formats = Object.entries(this.template.combine_formats ?? {}).filter(
+      ([, format]) => format
+    )
+    return JSON.stringify({
+      ...this.template,
+      combine_formats: Object.fromEntries(formats),
+      sample_document: this.previewDocId ?? null,
+    })
+  }
+
+  private markSaved() {
+    this.savedState = this.editorState()
+  }
+
   get pageTitle(): string {
     return this.isNew
       ? $localize`New OCR Template`
@@ -313,6 +340,7 @@ export class OcrTemplateEditorComponent implements OnInit, OnDestroy {
             this.previewDocId = t.sample_document
             this.loadPreview()
           }
+          this.markSaved()
         })
     } else {
       const qp = this.route.snapshot.queryParams
@@ -325,6 +353,7 @@ export class OcrTemplateEditorComponent implements OnInit, OnDestroy {
         this.previewDocId = docId
         this.loadPreview()
       }
+      this.markSaved()
     }
   }
 
@@ -896,6 +925,7 @@ export class OcrTemplateEditorComponent implements OnInit, OnDestroy {
         this.isNew = false
         this.selectedZoneIndex = idx
         this.saving = false
+        this.markSaved()
         this.toastService.showInfo($localize`OCR template saved.`)
         this.changeDetector.markForCheck()
       },