diff --git a/lib/philomena/images/image.ex b/lib/philomena/images/image.ex
index f1c416c5..3d559d09 100644
--- a/lib/philomena/images/image.ex
+++ b/lib/philomena/images/image.ex
@@ -326,8 +326,9 @@ defmodule Philomena.Images.Image do
     file_name_slug_fragment =
       tags
       |> Enum.map_join("_", & &1.slug)
-      |> String.replace("%", "")
-      |> String.replace("/", "")
+      |> String.to_charlist()
+      |> Enum.filter(&(&1 in ?a..?z or &1 in '0123456789_-'))
+      |> List.to_string()
       |> String.slice(0..150)
 
     file_name_cache = "#{image_id}__#{file_name_slug_fragment}"
diff --git a/lib/philomena_web/views/image_view.ex b/lib/philomena_web/views/image_view.ex
index 4fe58083..68517f1f 100644
--- a/lib/philomena_web/views/image_view.ex
+++ b/lib/philomena_web/views/image_view.ex
@@ -108,7 +108,7 @@ defmodule PhilomenaWeb.ImageView do
     root = image_url_root()
 
     view = if download, do: "download", else: "view"
-    filename = if short, do: image.id, else: image.file_name_cache
+    filename = if short, do: image.id, else: escaped_file_name(image)
 
     format =
       image.image_format
@@ -119,6 +119,10 @@ defmodule PhilomenaWeb.ImageView do
     "#{root}/#{view}/#{year}/#{month}/#{day}/#{filename}.#{format}"
   end
 
+  defp escaped_file_name(image) do
+    URI.encode(image.file_name_cache, &(&1 == ?+ or URI.char_unreserved?(&1)))
+  end
+
   def image_url_root do
     Application.get_env(:philomena, :image_url_root)
   end