diff --git a/mercurial/hgweb/webcommands.py b/mercurial/hgweb/webcommands.py
--- a/mercurial/hgweb/webcommands.py
+++ b/mercurial/hgweb/webcommands.py
@@ -930,6 +930,9 @@
                    "linenumber": "% 6d" % (lineno + 1),
                    "revdate": f.date()}
 
+    diffopts = webutil.difffeatureopts(req, web.repo.ui, 'annotate')
+    diffopts = {k: getattr(diffopts, k) for k in diffopts.defaults}
+
     return tmpl("fileannotate",
                 file=f,
                 annotate=annotate,
@@ -938,6 +941,7 @@
                 rename=webutil.renamelink(fctx),
                 permissions=fctx.manifest().flags(f),
                 ishead=int(ishead),
+                diffopts=diffopts,
                 **webutil.commonentry(web.repo, fctx))
 
 @webcommand('filelog')
diff --git a/mercurial/templates/gitweb/fileannotate.tmpl b/mercurial/templates/gitweb/fileannotate.tmpl
--- a/mercurial/templates/gitweb/fileannotate.tmpl
+++ b/mercurial/templates/gitweb/fileannotate.tmpl
@@ -62,6 +62,13 @@
 </div>
 
 <div class="page_path description">{desc|strip|escape|websub|nonempty}</div>
+
+{diffoptsform}
+
+<script type="text/javascript"{if(nonce, ' nonce="{nonce}"')}>
+    renderDiffOptsForm();
+</script>
+
 <div class="page_body">
 <table>
 <tbody class="sourcelines"
diff --git a/mercurial/templates/gitweb/map b/mercurial/templates/gitweb/map
--- a/mercurial/templates/gitweb/map
+++ b/mercurial/templates/gitweb/map
@@ -334,3 +334,19 @@
   </div>'
 searchhint = 'Find changesets by keywords (author, files, the commit message), revision
   number or hash, or <a href="{url|urlescape}help/revsets">revset expression</a>.'
+
+diffoptsform = '
+  <form id="diffopts-form"
+    data-ignorews="{if(get(diffopts, 'ignorews'), '1', '0')}"
+    data-ignorewsamount="{if(get(diffopts, 'ignorewsamount'), '1', '0')}"
+    data-ignorewseol="{if(get(diffopts, 'ignorewseol'), '1', '0')}"
+    data-ignoreblanklines="{if(get(diffopts, 'ignoreblanklines'), '1', '0')}">
+    <span>Ignore whitespace changes - </span>
+    <span>Everywhere:</span>
+    <input id="ignorews-checkbox" type="checkbox" />
+    <span>Within whitespace:</span>
+    <input id="ignorewsamount-checkbox" type="checkbox" />
+    <span>At end of lines:</span>
+    <input id="ignorewseol-checkbox" type="checkbox" />
+  </form>
+  </div>'
diff --git a/mercurial/templates/paper/fileannotate.tmpl b/mercurial/templates/paper/fileannotate.tmpl
--- a/mercurial/templates/paper/fileannotate.tmpl
+++ b/mercurial/templates/paper/fileannotate.tmpl
@@ -65,6 +65,12 @@
 </tr>
 </table>
 
+{diffoptsform}
+
+<script type="text/javascript"{if(nonce, ' nonce="{nonce}"')}>
+    renderDiffOptsForm();
+</script>
+
 <div class="overflow">
 <table class="bigtable">
 <thead>
diff --git a/mercurial/templates/paper/map b/mercurial/templates/paper/map
--- a/mercurial/templates/paper/map
+++ b/mercurial/templates/paper/map
@@ -251,3 +251,18 @@
   </form>'
 searchhint = 'Find changesets by keywords (author, files, the commit message), revision
   number or hash, or <a href="{url|urlescape}help/revsets">revset expression</a>.'
+
+diffoptsform = '
+  <form id="diffopts-form"
+    data-ignorews="{if(get(diffopts, 'ignorews'), '1', '0')}"
+    data-ignorewsamount="{if(get(diffopts, 'ignorewsamount'), '1', '0')}"
+    data-ignorewseol="{if(get(diffopts, 'ignorewseol'), '1', '0')}"
+    data-ignoreblanklines="{if(get(diffopts, 'ignoreblanklines'), '1', '0')}">
+    <span>Ignore whitespace changes - </span>
+    <span>Everywhere:</span>
+    <input id="ignorews-checkbox" type="checkbox" />
+    <span>Within whitespace:</span>
+    <input id="ignorewsamount-checkbox" type="checkbox" />
+    <span>At end of lines:</span>
+    <input id="ignorewseol-checkbox" type="checkbox" />
+  </form>'
diff --git a/mercurial/templates/static/mercurial.js b/mercurial/templates/static/mercurial.js
--- a/mercurial/templates/static/mercurial.js
+++ b/mercurial/templates/static/mercurial.js
@@ -434,6 +434,56 @@
     scrollHandler();
 }
 
+function renderDiffOptsForm() {
+    // We use URLSearchParams for query string manipulation. Old browsers don't
+    // support this API.
+    if (!("URLSearchParams" in window)) {
+        return;
+    }
+
+    var form = document.getElementById("diffopts-form");
+
+    var KEYS = [
+        "ignorews",
+        "ignorewsamount",
+        "ignorewseol",
+        "ignoreblanklines",
+    ];
+
+    var urlParams = new URLSearchParams(window.location.search);
+
+    function updateAndRefresh(e) {
+        var checkbox = e.target;
+        var name = checkbox.id.substr(0, checkbox.id.indexOf("-"));
+        urlParams.set(name, checkbox.checked ? "1" : "0");
+        window.location.search = urlParams.toString();
+    }
+
+    var allChecked = form.getAttribute("data-ignorews") == "1";
+
+    for (var i = 0; i < KEYS.length; i++) {
+        var key = KEYS[i];
+
+        var checkbox = document.getElementById(key + "-checkbox");
+        if (!checkbox) {
+            continue;
+        }
+
+        currentValue = form.getAttribute("data-" + key);
+        checkbox.checked = currentValue != "0";
+
+        // ignorews implies ignorewsamount and ignorewseol.
+        if (allChecked && (key == "ignorewsamount" || key == "ignorewseol")) {
+            checkbox.checked = true;
+            checkbox.disabled = true;
+        }
+
+        checkbox.addEventListener("change", updateAndRefresh, false);
+    }
+
+    form.style.display = 'block';
+}
+
 document.addEventListener('DOMContentLoaded', function() {
    process_dates();
 }, false);
diff --git a/mercurial/templates/static/style-gitweb.css b/mercurial/templates/static/style-gitweb.css
--- a/mercurial/templates/static/style-gitweb.css
+++ b/mercurial/templates/static/style-gitweb.css
@@ -97,6 +97,12 @@
 }
 div.annotate-info a { color: #0000FF; text-decoration: underline; }
 td.annotate:hover div.annotate-info { display: inline; }
+
+#diffopts-form {
+  padding-left: 8px;
+  display: none;
+}
+
 .linenr { color:#999999; text-decoration:none }
 div.rss_logo { float: right; white-space: nowrap; }
 div.rss_logo a {
diff --git a/mercurial/templates/static/style-paper.css b/mercurial/templates/static/style-paper.css
--- a/mercurial/templates/static/style-paper.css
+++ b/mercurial/templates/static/style-paper.css
@@ -226,6 +226,13 @@
 div.annotate-info a { color: #0000FF; }
 td.annotate:hover div.annotate-info { display: inline; }
 
+#diffopts-form {
+  font-size: smaller;
+  color: #424242;
+  padding-bottom: 10px;
+  display: none;
+}
+
 .source, .sourcefirst {
   font-family: monospace;
   white-space: pre;
diff --git a/tests/test-hgweb.t b/tests/test-hgweb.t
--- a/tests/test-hgweb.t
+++ b/tests/test-hgweb.t
@@ -340,7 +340,7 @@
 
   $ get-with-headers.py --twice localhost:$HGPORT 'static/style-gitweb.css' - date etag server
   200 Script output follows
-  content-length: 9007
+  content-length: 9066
   content-type: text/css
   
   body { font-family: sans-serif; font-size: 12px; border:solid #d9d8d1; border-width:1px; margin:10px; background: white; color: black; }
@@ -442,6 +442,12 @@
   }
   div.annotate-info a { color: #0000FF; text-decoration: underline; }
   td.annotate:hover div.annotate-info { display: inline; }
+  
+  #diffopts-form {
+    padding-left: 8px;
+    display: none;
+  }
+  
   .linenr { color:#999999; text-decoration:none }
   div.rss_logo { float: right; white-space: nowrap; }
   div.rss_logo a {