diff --git a/src/core/document.js b/src/core/document.js
index 1cce067ab..4736a2839 100644
--- a/src/core/document.js
+++ b/src/core/document.js
@@ -1050,6 +1050,9 @@ class PDFDocument {
     }
 
     const ids = calculationOrder.filter(isRef).map(ref => ref.toString());
+    if (ids.length === 0) {
+      return shadow(this, "calculationOrderIds", null);
+    }
     return shadow(this, "calculationOrderIds", ids);
   }
 }
diff --git a/src/scripting_api/event.js b/src/scripting_api/event.js
index f96b0f757..542f16121 100644
--- a/src/scripting_api/event.js
+++ b/src/scripting_api/event.js
@@ -150,7 +150,7 @@ class EventDispatcher {
   }
 
   calculateNow() {
-    if (this._calculationOrder.length === 0) {
+    if (!this._calculationOrder) {
       return;
     }
     const first = this._calculationOrder[0];
@@ -160,7 +160,7 @@ class EventDispatcher {
   }
 
   runCalculate(source, event) {
-    if (this._calculationOrder.length === 0) {
+    if (!this._calculationOrder) {
       return;
     }
 
diff --git a/test/unit/document_spec.js b/test/unit/document_spec.js
index 57ab01542..cde9f5105 100644
--- a/test/unit/document_spec.js
+++ b/test/unit/document_spec.js
@@ -187,6 +187,14 @@ describe("document", function () {
       acroForm.set("CO", []);
       pdfDocument = getDocument(acroForm);
       expect(pdfDocument.calculationOrderIds).toEqual(null);
+
+      acroForm.set("CO", ["1", "2"]);
+      pdfDocument = getDocument(acroForm);
+      expect(pdfDocument.calculationOrderIds).toEqual(null);
+
+      acroForm.set("CO", ["1", Ref.get(1, 0), "2"]);
+      pdfDocument = getDocument(acroForm);
+      expect(pdfDocument.calculationOrderIds).toEqual(["1R"]);
     });
 
     it("should get field objects array or null", async function () {