diff --git a/src/index.ts b/src/index.ts
index bc3f84b..0ad11a9 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -52,11 +52,17 @@ interface CreateNodeHelpersParams {
 }
 
 /**
- * A record that can be globally identified using a combination of `id` and
- * `type` fields.
+ * A value that can be converted to a string using `toString()`.
+ */
+export interface Stringable {
+  toString(): string
+}
+
+/**
+ * A record that can be globally identified using its `id` field.
  */
 export interface IdentifiableRecord {
-  id: string
+  id: Stringable
   // eslint-disable-next-line @typescript-eslint/no-explicit-any
   [key: string]: any
 }
@@ -144,7 +150,7 @@ export const createNodeHelpers = ({
   ): gatsby.NodeInput => {
     const res = {
       ...node,
-      id: createNodeId(...nameParts, node.id),
+      id: createNodeId(...nameParts, node.id.toString()),
       internal: {
         type: createTypeName(...nameParts),
         contentDigest: gatsbyCreateContentDigest(node),
diff --git a/test/index.test.ts b/test/index.test.ts
index 441077c..ea35826 100644
--- a/test/index.test.ts
+++ b/test/index.test.ts
@@ -100,6 +100,16 @@ describe('createNodeFactory', () => {
     expect(nodeInput.id).toBe(`createNodeId(typePrefix TypeName ${node.id})`)
   })
 
+  test('accepts non-string node IDs', () => {
+    const modifiedNode = { ...node, id: [1, 2, 3] }
+    const modifiedNodeInput = fn(modifiedNode)
+
+    expect(modifiedNodeInput.id).toBe(
+      `createNodeId(typePrefix TypeName ${modifiedNode.id})`,
+    )
+    expect(modifiedNodeInput.fieldPrefixId).toBe(modifiedNode.id)
+  })
+
   test('adds internal field with required Gatsby fields', () => {
     expect(nodeInput.internal).toEqual({
       type: 'TypePrefixTypeName',