diff --git a/CHANGELOG.md b/CHANGELOG.md
index e3694f847..b1e4141ed 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,5 @@
+- Added `Image Size` setting for the catalog.
+
 ### 3.17.1 - *2014-02-10*
 
 - `Index Mode` and `Index Sort` have been moved out of the header's menu into the index page.
diff --git a/css/style.css b/css/style.css
index 23ba8e1aa..63ff8fba3 100644
--- a/css/style.css
+++ b/css/style.css
@@ -415,12 +415,18 @@ a[href="javascript:;"] {
   text-align: left;
   flex-direction: column;
   align-items: center;
-  width: 165px;
   margin: 0 2px 5px;
-  max-height: 320px;
   word-break: break-word;
   vertical-align: top;
 }
+.catalog-small .catalog-thread {
+  width: 165px;
+  max-height: 320px;
+}
+.catalog-large .catalog-thread {
+  width: 270px;
+  max-height: 410px;
+}
 .thumb {
   flex-shrink: 0;
   position: relative;
diff --git a/html/General/Index-navlinks.html b/html/General/Index-navlinks.html
index 4dc35c53f..485d8489b 100644
--- a/html/General/Index-navlinks.html
+++ b/html/General/Index-navlinks.html
@@ -17,3 +17,8 @@
   <option value="replycount">Reply count</option>
   <option value="filecount">File count</option>
 </select>
+<select id="index-size" name="Index Size">
+  <option disabled>Image Size</option>
+  <option value="small">Small</option>
+  <option value="large">Large</option>
+</select>
diff --git a/src/General/Build.coffee b/src/General/Build.coffee
index 027f09515..51e2fd9c4 100644
--- a/src/General/Build.coffee
+++ b/src/General/Build.coffee
@@ -294,9 +294,8 @@ Build =
       $.addClass thumb, 'deleted-file'
     else if thread.OP.file
       src = thread.OP.file.thumbURL
-      max = Math.max data.tn_w, data.tn_h
-      thumb.style.width  = data.tn_w * 150 / max + 'px'
-      thumb.style.height = data.tn_h * 150 / max + 'px'
+      thumb.dataset.width  = data.tn_w
+      thumb.dataset.height = data.tn_h
     else
       src = "#{staticPath}nofile.png"
       $.addClass thumb, 'no-file'
diff --git a/src/General/Config.coffee b/src/General/Config.coffee
index b836adbdd..3e127e782 100644
--- a/src/General/Config.coffee
+++ b/src/General/Config.coffee
@@ -141,6 +141,7 @@ Config =
     'Index Mode': 'paged'
     'Previous Index Mode': 'paged'
     'Index Sort': 'bump'
+    'Index Size': 'small'
     'Threads per Page': 0
     'Show Replies': true
     'Anchor Hidden Threads': true
diff --git a/src/General/Index.coffee b/src/General/Index.coffee
index bab27411b..f341cb81f 100644
--- a/src/General/Index.coffee
+++ b/src/General/Index.coffee
@@ -70,14 +70,16 @@ Index =
     @hideLabel   = $ '#hidden-label', @navLinks
     @selectMode  = $ '#index-mode',   @navLinks
     @selectSort  = $ '#index-sort',   @navLinks
+    @selectSize  = $ '#index-size',   @navLinks
     $.on @searchInput, 'input', @onSearchInput
     $.on $('#index-search-clear', @navLinks), 'click', @clearSearch
     $.on $('#hidden-toggle a',    @navLinks), 'click', @cb.toggleHiddenThreads
-    for select in [@selectMode, @selectSort]
+    for select in [@selectMode, @selectSort, @selectSize]
       select.value = Conf[select.name]
       $.on select, 'change', $.cb.value
     $.on @selectMode, 'change', @cb.mode
     $.on @selectSort, 'change', @cb.sort
+    $.on @selectSize, 'change', @cb.size
 
     @root = $.el 'div', className: 'board'
     @pagelist = $.el 'div',
@@ -87,7 +89,10 @@ Index =
     @currentPage = @getCurrentPage()
     $.on window, 'popstate', @cb.popstate
     $.on @pagelist, 'click', @cb.pageNav
+
     @cb.toggleCatalogMode()
+    @cb.size()
+
     $.asap (-> $('.board', doc) or d.readyState isnt 'loading'), ->
       board = $ '.board'
       $.replace board, Index.root
@@ -230,6 +235,17 @@ Index =
     sort: ->
       Index.sort()
       Index.buildIndex()
+    size: (e) ->
+      if Conf['Index Mode'] isnt 'catalog'
+        $.rmClass Index.root, 'catalog-small'
+        $.rmClass Index.root, 'catalog-large'
+      else if Conf['Index Size'] is 'small'
+        $.addClass Index.root, 'catalog-small'
+        $.rmClass Index.root,  'catalog-large'
+      else
+        $.addClass Index.root, 'catalog-large'
+        $.rmClass Index.root,  'catalog-small'
+      Index.buildIndex() if e
     threadsNum: ->
       return unless Conf['Index Mode'] is 'paged'
       Index.buildPagelist()
@@ -498,6 +514,17 @@ Index =
       catalogThreads.push new CatalogThread Build.catalogThread(thread), thread
     Main.callbackNodes CatalogThread, catalogThreads
     threads.map (thread) -> thread.catalogView.nodes.root
+  sizeCatalogViews: (nodes) ->
+    # XXX When browsers support CSS3 attr(), use it instead.
+    size = if Conf['Index Size'] is 'small' then 150 else 250
+    for node in nodes
+      thumb = $ '.thumb', node
+      {width, height} = thumb.dataset
+      continue unless width
+      ratio = size / Math.max width, height
+      thumb.style.width  = width  * ratio + 'px'
+      thumb.style.height = height * ratio + 'px'
+    return
   sort: ->
     switch Conf['Index Sort']
       when 'bump'
@@ -539,6 +566,7 @@ Index =
         nodes = Index.sortedNodes[nodesPerPage * pageNum ... nodesPerPage * (pageNum + 1)]
       when 'catalog'
         nodes = Index.buildCatalogViews()
+        Index.sizeCatalogViews nodes
       else
         nodes = Index.sortedNodes
     $.rmAll Index.root