diff --git a/js/common/view/FluidDensityControlNode.ts b/js/common/view/FluidDensityControlNode.ts
index cf747f12..7816e556 100644
--- a/js/common/view/FluidDensityControlNode.ts
+++ b/js/common/view/FluidDensityControlNode.ts
@@ -33,7 +33,10 @@ type ParentOptions = WithRequired<Partial<ComboNumberControlOptions<Material>>,
 type DensityControlNodeOptions = SelfOptions & ParentOptions;
 
 const FALLBACK_NODE = new Text( DensityBuoyancyCommonStrings.whatIsTheFluidDensityStringProperty, {
-  font: new PhetFont( 14 )
+  font: new PhetFont( 14 ),
+
+  // estimate as the same max width as the combo box below
+  maxWidth: 210
 } );
 
 export default class FluidDensityControlNode extends ComboNumberControl<Material> {
diff --git a/js/common/view/GravityControlNode.ts b/js/common/view/GravityControlNode.ts
index cdc2daee..767a9f2e 100644
--- a/js/common/view/GravityControlNode.ts
+++ b/js/common/view/GravityControlNode.ts
@@ -18,7 +18,10 @@ import GravityProperty from '../model/GravityProperty.js';
 import ComboNumberControl from './ComboNumberControl.js';
 
 const FALLBACK_NODE = new Text( DensityBuoyancyCommonStrings.whatIsTheValueOfGravityStringProperty, {
-  font: new PhetFont( 14 )
+  font: new PhetFont( 14 ),
+
+  // estimate as the same max width as the combo box below
+  maxWidth: 210
 } );
 
 export default class GravityControlNode extends ComboNumberControl<Gravity> {