diff --git a/src/wp-admin/css/common.css b/src/wp-admin/css/common.css
index 3a11a58e30..1702e7736c 100644
--- a/src/wp-admin/css/common.css
+++ b/src/wp-admin/css/common.css
@@ -3716,6 +3716,23 @@ img {
 	}
 }
 
+.options-media-php br {
+	display: none;
+}
+
+@media screen and (max-width: 375px) {
+	.options-media-php input[type="number"][name*="_size_"] {
+		margin: 5px 0;
+	}
+	.options-media-php label[for*="_size_h"]:before {
+		content: '';
+		display: block;
+	}
+	.options-media-php br {
+		display: block;
+	}
+}
+
 @media screen and (max-width: 320px) {
 	/* Prevent default center alignment and larger font for the Right Now widget when
 	   the network dashboard is viewed on a small mobile device. */
diff --git a/src/wp-admin/css/forms.css b/src/wp-admin/css/forms.css
index 6b36d20769..665e6c0af8 100644
--- a/src/wp-admin/css/forms.css
+++ b/src/wp-admin/css/forms.css
@@ -1220,7 +1220,7 @@ table.form-table td .updated p {
 	input[type="number"].small-text,
 	.form-table input[type="text"].small-text {
 		width: auto;
-		max-width: 55px;
+		max-width: 4.375em; /* 70px, enough for 4 digits to fit comfortably */
 		display: inline;
 		padding: 3px 6px;
 		margin: 0 3px;
diff --git a/src/wp-admin/options-media.php b/src/wp-admin/options-media.php
index a948936e60..a0f8a9ebdb 100644
--- a/src/wp-admin/options-media.php
+++ b/src/wp-admin/options-media.php
@@ -55,9 +55,9 @@ include( ABSPATH . 'wp-admin/admin-header.php' );
 <label for="thumbnail_size_w"><?php _e('Width'); ?></label>
 <input name="thumbnail_size_w" type="number" step="1" min="0" id="thumbnail_size_w" value="<?php form_option('thumbnail_size_w'); ?>" class="small-text" />
 <label for="thumbnail_size_h"><?php _e('Height'); ?></label>
-<input name="thumbnail_size_h" type="number" step="1" min="0" id="thumbnail_size_h" value="<?php form_option('thumbnail_size_h'); ?>" class="small-text" /><br />
-<input name="thumbnail_crop" type="checkbox" id="thumbnail_crop" value="1" <?php checked('1', get_option('thumbnail_crop')); ?>/>
-<label for="thumbnail_crop"><?php _e('Crop thumbnail to exact dimensions (normally thumbnails are proportional)'); ?></label>
+<input name="thumbnail_size_h" type="number" step="1" min="0" id="thumbnail_size_h" value="<?php form_option('thumbnail_size_h'); ?>" class="small-text" />
+<p><input name="thumbnail_crop" type="checkbox" id="thumbnail_crop" value="1" <?php checked('1', get_option('thumbnail_crop')); ?>/>
+<label for="thumbnail_crop"><?php _e('Crop thumbnail to exact dimensions (normally thumbnails are proportional)'); ?></label></p>
 </td>
 </tr>
 
@@ -66,6 +66,7 @@ include( ABSPATH . 'wp-admin/admin-header.php' );
 <td><fieldset><legend class="screen-reader-text"><span><?php _e('Medium size'); ?></span></legend>
 <label for="medium_size_w"><?php _e('Max Width'); ?></label>
 <input name="medium_size_w" type="number" step="1" min="0" id="medium_size_w" value="<?php form_option('medium_size_w'); ?>" class="small-text" />
+<br />
 <label for="medium_size_h"><?php _e('Max Height'); ?></label>
 <input name="medium_size_h" type="number" step="1" min="0" id="medium_size_h" value="<?php form_option('medium_size_h'); ?>" class="small-text" />
 </fieldset></td>
@@ -76,6 +77,7 @@ include( ABSPATH . 'wp-admin/admin-header.php' );
 <td><fieldset><legend class="screen-reader-text"><span><?php _e('Large size'); ?></span></legend>
 <label for="large_size_w"><?php _e('Max Width'); ?></label>
 <input name="large_size_w" type="number" step="1" min="0" id="large_size_w" value="<?php form_option('large_size_w'); ?>" class="small-text" />
+<br />
 <label for="large_size_h"><?php _e('Max Height'); ?></label>
 <input name="large_size_h" type="number" step="1" min="0" id="large_size_h" value="<?php form_option('large_size_h'); ?>" class="small-text" />
 </fieldset></td>