diff --git a/apps/web/src/views/detail.ejs b/apps/web/src/views/detail.ejs
index de1bced..045ca66 100644
--- a/apps/web/src/views/detail.ejs
+++ b/apps/web/src/views/detail.ejs
@@ -173,6 +173,48 @@
     const _initialQuery = <%~ JSON.stringify(m.query || null) %>;
     <%~ include('./partials/monitor-form-js') %>
 
+    // ── Syntax highlighting ────────────────────────────────────────
+    function highlightJson(str) {
+      try { str = JSON.stringify(JSON.parse(str), null, 2); } catch {}
+      return escapeHtml(str).replace(
+        /("(?:\\.|[^"\\])*")\s*:/g,
+        '<span class="text-blue-400">$1</span>:'
+      ).replace(
+        /:\s*("(?:\\.|[^"\\])*")/g,
+        ': <span class="text-green-400">$1</span>'
+      ).replace(
+        /:\s*(true|false)/g,
+        ': <span class="text-yellow-400">$1</span>'
+      ).replace(
+        /:\s*(null)/g,
+        ': <span class="text-gray-500">$1</span>'
+      ).replace(
+        /:\s*(-?\d+\.?\d*(?:[eE][+-]?\d+)?)/g,
+        ': <span class="text-purple-400">$1</span>'
+      );
+    }
+
+    function highlightXml(str) {
+      return escapeHtml(str)
+        .replace(/&lt;(\/?)([\w:-]+)/g, '&lt;$1<span class="text-red-400">$2</span>')
+        .replace(/([\w:-]+)(=)(&quot;[^&]*&quot;)/g, '<span class="text-yellow-400">$1</span>$2<span class="text-green-400">$3</span>');
+    }
+
+    function highlightBody(body, contentType) {
+      const ct = (contentType || '').toLowerCase();
+      if (ct.includes('json')) return highlightJson(body);
+      if (ct.includes('xml') || ct.includes('html')) return highlightXml(body);
+      return escapeHtml(body);
+    }
+
+    function getContentType(headers) {
+      if (!headers) return '';
+      for (const [k, v] of Object.entries(headers)) {
+        if (k.toLowerCase() === 'content-type') return String(v);
+      }
+      return '';
+    }
+
     // ── Ping detail modal ──────────────────────────────────────────
     function openPingModal(ping) {
       const modalBody = document.getElementById('ping-modal-body');
@@ -223,9 +265,11 @@
       }
 
       // Response body — loaded on demand
+      const contentType = getContentType(headers);
+      const ctLabel = contentType ? ` <span class="text-gray-600">(${escapeHtml(contentType.split(';')[0].trim())})</span>` : '';
       html += '<div id="ping-body-section">';
       if (ping.id) {
-        html += '<div class="text-xs text-gray-500 mb-1">Response Body</div>';
+        html += `<div class="text-xs text-gray-500 mb-1">Response Body${ctLabel}</div>`;
         html += '<div id="ping-body-content" class="bg-gray-800/50 border border-border-subtle rounded-lg px-3 py-2 text-xs font-mono text-gray-500 min-h-[2rem] flex items-center">Loading...</div>';
       }
       html += '</div>';
@@ -236,12 +280,13 @@
 
       // Fetch body asynchronously
       if (ping.id) {
+        const ct = getContentType(headers);
         api(`/pings/${ping.id}/body`).then(data => {
           const el = document.getElementById('ping-body-content');
           if (!el) return;
           if (data.body) {
             el.className = 'bg-gray-800/50 border border-border-subtle rounded-lg px-3 py-2 text-xs font-mono text-gray-300 whitespace-pre-wrap break-all max-h-80 overflow-y-auto';
-            el.textContent = data.body;
+            el.innerHTML = highlightBody(data.body, ct);
           } else {
             el.textContent = 'No body stored';
           }