diff --git a/docs/changelog/126256.yaml b/docs/changelog/126256.yaml
new file mode 100644
index 0000000000000..8db9535176c64
--- /dev/null
+++ b/docs/changelog/126256.yaml
@@ -0,0 +1,5 @@
+pr: 126256
+summary: Adjust REST test code to accommodate changes to calculation of "model bytes" and "peak mode bytes" values.
+area: Machine Learning
+type: enhancement
+issues: []
diff --git a/x-pack/plugin/ml/qa/native-multi-node-tests/src/javaRestTest/java/org/elasticsearch/xpack/ml/integration/AutodetectMemoryLimitIT.java b/x-pack/plugin/ml/qa/native-multi-node-tests/src/javaRestTest/java/org/elasticsearch/xpack/ml/integration/AutodetectMemoryLimitIT.java
index fb6b48f33fc16..c4574a3115624 100644
--- a/x-pack/plugin/ml/qa/native-multi-node-tests/src/javaRestTest/java/org/elasticsearch/xpack/ml/integration/AutodetectMemoryLimitIT.java
+++ b/x-pack/plugin/ml/qa/native-multi-node-tests/src/javaRestTest/java/org/elasticsearch/xpack/ml/integration/AutodetectMemoryLimitIT.java
@@ -78,7 +78,7 @@ public void testTooManyPartitions() throws Exception {
         // Assert we haven't violated the limit too much
         GetJobsStatsAction.Response.JobStats jobStats = getJobStats(job.getId()).get(0);
         ModelSizeStats modelSizeStats = jobStats.getModelSizeStats();
-        assertThat(modelSizeStats.getModelBytes(), lessThan(32000000L));
+        assertThat(modelSizeStats.getModelBytes(), lessThan(50300000L));
         assertThat(modelSizeStats.getModelBytes(), greaterThan(24000000L));
         assertThat(
             modelSizeStats.getMemoryStatus(),
@@ -125,7 +125,7 @@ public void testTooManyByFields() throws Exception {
         // Assert we haven't violated the limit too much
         GetJobsStatsAction.Response.JobStats jobStats = getJobStats(job.getId()).get(0);
         ModelSizeStats modelSizeStats = jobStats.getModelSizeStats();
-        assertThat(modelSizeStats.getModelBytes(), lessThan(35000000L));
+        assertThat(modelSizeStats.getModelBytes(), lessThan(45000000L));
         assertThat(modelSizeStats.getModelBytes(), greaterThan(25000000L));
         assertThat(modelSizeStats.getMemoryStatus(), equalTo(ModelSizeStats.MemoryStatus.HARD_LIMIT));
     }
@@ -176,7 +176,7 @@ public void testTooManyByAndOverFields() throws Exception {
         // Assert we haven't violated the limit too much
         GetJobsStatsAction.Response.JobStats jobStats = getJobStats(job.getId()).get(0);
         ModelSizeStats modelSizeStats = jobStats.getModelSizeStats();
-        assertThat(modelSizeStats.getModelBytes(), lessThan(33000000L));
+        assertThat(modelSizeStats.getModelBytes(), lessThan(72000000L));
         assertThat(modelSizeStats.getModelBytes(), greaterThan(24000000L));
         assertThat(modelSizeStats.getMemoryStatus(), equalTo(ModelSizeStats.MemoryStatus.HARD_LIMIT));
     }
@@ -226,7 +226,7 @@ public void testManyDistinctOverFields() throws Exception {
         GetJobsStatsAction.Response.JobStats jobStats = getJobStats(job.getId()).get(0);
         ModelSizeStats modelSizeStats = jobStats.getModelSizeStats();
         assertThat(modelSizeStats.getModelBytes(), lessThan(120500000L));
-        assertThat(modelSizeStats.getModelBytes(), greaterThan(90000000L));
+        assertThat(modelSizeStats.getModelBytes(), greaterThan(70000000L));
         assertThat(modelSizeStats.getMemoryStatus(), equalTo(ModelSizeStats.MemoryStatus.HARD_LIMIT));
     }