diff --git a/Library/Homebrew/download_strategy.rb b/Library/Homebrew/download_strategy.rb
index 79623ff2bf..58a79b181f 100644
--- a/Library/Homebrew/download_strategy.rb
+++ b/Library/Homebrew/download_strategy.rb
@@ -470,25 +470,29 @@ class CurlDownloadStrategy < AbstractFileDownloadStrategy
 
         ohai "Downloading #{url}"
 
-        use_cached_location = cached_location.exist?
+        cached_location_valid = cached_location.exist?
         v = version
-        use_cached_location = false if v.is_a?(Cask::DSL::Version) && v.latest?
+        cached_location_valid = false if v.is_a?(Cask::DSL::Version) && v.latest?
 
-        resolved_url, _, last_modified, _, is_redirection = begin
+        resolved_url, _, last_modified, file_size, is_redirection = begin
           resolve_url_basename_time_file_size(url, timeout: Utils::Timer.remaining!(end_time))
         rescue ErrorDuringExecution
-          raise unless use_cached_location
+          raise unless cached_location_valid
         end
 
         # Authorization is no longer valid after redirects
         meta[:headers]&.delete_if { |header| header.start_with?("Authorization") } if is_redirection
 
-        # The cached location is no longer fresh if Last-Modified is after the file's timestamp
-        if cached_location.exist? && last_modified && last_modified > cached_location.mtime
-          use_cached_location = false
+        # The cached location is no longer fresh if either:
+        # - Last-Modified value is newer than the file's timestamp
+        # - Content-Length value is different than the file's size
+        cached_location_valid = if cached_location_valid
+          newer_last_modified = last_modified && last_modified > cached_location.mtime
+          different_file_size = file_size && file_size != cached_location.size
+          !(newer_last_modified || different_file_size)
         end
 
-        if use_cached_location
+        if cached_location_valid
           puts "Already downloaded: #{cached_location}"
         else
           begin