diff --git a/portfolio/site.hs b/portfolio/site.hs
index 5c2012c..c0505d4 100644
--- a/portfolio/site.hs
+++ b/portfolio/site.hs
@@ -147,6 +147,7 @@ main = hakyll $ do
 
             let plamoCtx =
                     listField  "kits" (kitCtx lang) (return kits) <>
+                    lastUpdateField lang <>
                     langDict lang <>
                     defaultContext
 
@@ -183,6 +184,7 @@ main = hakyll $ do
                     listField "binding_particles" (postCtx lang) (return binding_particles) <>
                     listField "verbs" (postCtx lang) (return verbs) <>
                     listField "other" (postCtx lang) (return other) <>
+                    lastUpdateField lang <>
                     langDict lang <>
                     defaultContext
 
@@ -210,6 +212,7 @@ main = hakyll $ do
             let radioCtx =
                     listField "antenna"   (postCtx lang) (return antenna) <>
                     listField "fielddays" (postCtx lang) (return fielddays) <>
+                    lastUpdateField lang <>
                     langDict lang <>
                     defaultContext
 
@@ -235,6 +238,7 @@ main = hakyll $ do
 
             let softwareCtx =
                     listField "projects" (postCtx lang) (return projects) <>
+                    lastUpdateField lang <>
                     langDict lang <>
                     defaultContext
 
@@ -259,6 +263,7 @@ main = hakyll $ do
 
             let softwareCtx =
                     listField "blazorPages"  (postCtx lang) (return blazorPages) <>
+                    lastUpdateField lang <>
                     langDict lang <>
                     defaultContext
 
@@ -283,6 +288,7 @@ main = hakyll $ do
 
             let softwareCtx =
                     listField "elmPages"     (postCtx lang) (return elmPages) <>
+                    lastUpdateField lang <>
                     langDict lang <>
                     defaultContext
 
@@ -307,6 +313,7 @@ main = hakyll $ do
 
             let softwareCtx =
                     listField "haskellPages" (postCtx lang) (return haskellPages) <>
+                    lastUpdateField lang <>
                     langDict lang <>
                     defaultContext
 
@@ -331,6 +338,7 @@ main = hakyll $ do
 
             let equipmentCtx =
                     listField "equipment" (postCtx lang) (return equipment) <>
+                    lastUpdateField lang <>
                     langDict lang <>
                     defaultContext
 
@@ -352,6 +360,7 @@ main = hakyll $ do
             let lang = fromMaybe "en" language
 
             let paintsCtx =
+                    lastUpdateField lang <>
                     langDict lang <>
                     defaultContext
 
@@ -376,6 +385,7 @@ main = hakyll $ do
 
             let eventsCtx =
                     listField "events"  (postCtx lang) (return events)  <>
+                    lastUpdateField lang <>
                     langDict lang <>
                     defaultContext
 
@@ -400,6 +410,7 @@ main = hakyll $ do
 
             let postsCtx =
                     listField "posts"  (postCtx lang) (return posts)  <>
+                    lastUpdateField lang <>
                     langDict lang <>
                     defaultContext
 
@@ -438,6 +449,7 @@ main = hakyll $ do
                     -- (<> is the modern version of `mappend`.)
                     listField "posts"  (postCtx lang) (return posts)  <>
                     listField "events" (postCtx lang) (return events) <>
+                    lastUpdateField lang <>
                     langDict lang <>
                     defaultContext
 
@@ -453,6 +465,7 @@ main = hakyll $ do
 --------------------------------------------------------------------------------
 staticPageContext :: Context String
 staticPageContext =
+        lastUpdateField "en" <>
         langDict "en" <>
         defaultContext
 
@@ -493,6 +506,13 @@ formatDate lang s =
         Just day -> formatTime (localeFor lang) (formatStringFor lang) day
         Nothing  -> s
 
+lastUpdateField :: String -> Context a
+lastUpdateField lang =
+    field "last-update" $ \_ -> do
+        now <- unsafeCompiler getCurrentTime
+        let dayString = formatTime defaultTimeLocale "%Y-%m-%d" now
+        pure $ formatDate lang dayString
+
 postCtx :: String -> Context String
 postCtx language =
     let
@@ -508,6 +528,7 @@ postCtx language =
         dateField "date" "%e %B %Y" <>
         constField "language" language <>
         formattedDateField <>
+        lastUpdateField language <>
         langDict language <>
         defaultContext
 
@@ -577,6 +598,7 @@ langDict "nl" =
     constField "table-plamo-venue" "Venue" <>
     constField "table-plamo-location" "Locatie" <>
     constField "footer" "Deze website is gebouwd met <a href=\"http://jaspervdj.be/hakyll\" target=\"_blank\" rel=\"noopener noreferrer\">Hakyll</a> en <a href=\"https://getbootstrap.com/\" target=\"_blank\" rel=\"noopener noreferrer\">Bootstrap</a>, met <a href=\"https://www.docker.com/\" target=\"_blank\" rel=\"noopener noreferrer\">Docker</a> containers en <a href=\"https://www.nginx.com/\" target=\"_blank\" rel=\"noopener noreferrer\">Nginx</a> op een <a href=\"https://www.strato.nl/server/vps-linux/\" target=\"_blank\" rel=\"noopener noreferrer\">Strato VPS</a>." <>
+    constField "last-update-text" "Website geüpdate" <>
     mempty
 
 langDict "jp" =
@@ -625,6 +647,7 @@ langDict "jp" =
     constField "table-plamo-venue" "購入場所" <>
     constField "table-plamo-location" "場所" <>
     constField "footer" "<a href=\"http://jaspervdj.be/hakyll\" target=\"_blank\" rel=\"noopener noreferrer\">Hakyll</a> と <a href=\"https://getbootstrap.com/\" target=\"_blank\" rel=\"noopener noreferrer\">Bootstrap</a> を使用し、<a href=\"https://www.docker.com/\" target=\"_blank\" rel=\"noopener noreferrer\">Docker</a> コンテナと <a href=\"https://www.nginx.com/\" target=\"_blank\" rel=\"noopener noreferrer\">Nginx</a> を用いた <a href=\"https://www.strato.nl/server/vps-linux/\" target=\"_blank\" rel=\"noopener noreferrer\">Strato VPS</a> 上で誇りをもって生成されています。" <>
+    constField "last-update-text" "最終更新" <>
     mempty
 
 langDict "en" =
@@ -673,6 +696,7 @@ langDict "en" =
     constField "table-plamo-venue" "Venue" <>
     constField "table-plamo-location" "Location" <>
     constField "footer" "Site proudly generated by <a href=\"http://jaspervdj.be/hakyll\" target=\"_blank\" rel=\"noopener noreferrer\">Hakyll</a> and <a href=\"https://getbootstrap.com/\" target=\"_blank\" rel=\"noopener noreferrer\">Bootstrap</a>, using <a href=\"https://www.docker.com/\" target=\"_blank\" rel=\"noopener noreferrer\">Docker</a> containers with <a href=\"https://www.nginx.com/\" target=\"_blank\" rel=\"noopener noreferrer\">Nginx</a> on a <a href=\"https://www.strato.nl/server/vps-linux/\" target=\"_blank\" rel=\"noopener noreferrer\">Strato VPS</a>." <>
+    constField "last-update-text" "Last update" <>
     mempty
 
 langDict _ = mempty
diff --git a/portfolio/templates/default.html b/portfolio/templates/default.html
index d62959b..a371b56 100644
--- a/portfolio/templates/default.html
+++ b/portfolio/templates/default.html
@@ -23,7 +23,7 @@
         </div>
 
         <footer class="bg-body-tertiary">
-            $footer$
+            $footer$ <br/> $last-update-text$: $last-update$
         </footer>
 
     </body>