diff --git a/packages/react-dom/src/__tests__/ReactDOMFizzServerEdge-test.js b/packages/react-dom/src/__tests__/ReactDOMFizzServerEdge-test.js
index 91f0774aa661e..06b3c61ce3ce5 100644
--- a/packages/react-dom/src/__tests__/ReactDOMFizzServerEdge-test.js
+++ b/packages/react-dom/src/__tests__/ReactDOMFizzServerEdge-test.js
@@ -138,7 +138,7 @@ describe('ReactDOMFizzServerEdge', () => {
     if (gate(flags => flags.enableFizzBlockingRender)) {
       expect(errors.length).toBe(1);
       expect(errors[0].message).toContain(
-        'This rendered a large document (>512) without any Suspense boundaries around most of it.',
+        'This rendered a large document (>512 kB) without any Suspense boundaries around most of it.',
       );
     } else {
       expect(errors.length).toBe(0);
diff --git a/packages/react-server/src/ReactFizzServer.js b/packages/react-server/src/ReactFizzServer.js
index bff81ce607989..2995b498f4971 100644
--- a/packages/react-server/src/ReactFizzServer.js
+++ b/packages/react-server/src/ReactFizzServer.js
@@ -5946,7 +5946,7 @@ function flushCompletedQueues(
           const error = new Error(
             'This rendered a large document (>' +
               maxSizeKb +
-              ') without any Suspense ' +
+              ' kB) without any Suspense ' +
               'boundaries around most of it. That can delay initial paint longer than ' +
               'necessary. To improve load performance, add a <Suspense> or <SuspenseList> ' +
               'around the content you expect to be below the header or below the fold. ' +
diff --git a/scripts/error-codes/codes.json b/scripts/error-codes/codes.json
index 7e709903a841d..a3147f4dde3b3 100644
--- a/scripts/error-codes/codes.json
+++ b/scripts/error-codes/codes.json
@@ -546,5 +546,5 @@
   "558": "Client rendering an Activity suspended it again. This is a bug in React.",
   "559": "Expected to find a host node. This is a bug in React.",
   "560": "Cannot use a startGestureTransition() with a comment node root.",
-  "561": "This rendered a large document (>%s) without any Suspense boundaries around most of it. That can delay initial paint longer than necessary. To improve load performance, add a <Suspense> or <SuspenseList> around the content you expect to be below the header or below the fold. In the meantime, the content will deopt to paint arbitrary incomplete pieces of HTML."
+  "561": "This rendered a large document (>%s kB) without any Suspense boundaries around most of it. That can delay initial paint longer than necessary. To improve load performance, add a <Suspense> or <SuspenseList> around the content you expect to be below the header or below the fold. In the meantime, the content will deopt to paint arbitrary incomplete pieces of HTML."
 }