diff --git a/public/index.html b/public/index.html
index a540662..416264e 100644
--- a/public/index.html
+++ b/public/index.html
@@ -508,7 +508,7 @@
   <script defer src="/js/documents.js"></script>
   <script defer src="/js/calc-math.js"></script>
   <script defer src="/js/drugs-loader.js"></script>
-  <script defer src="/js/calculators.js"></script>
+  <script type="module" src="/js/calculators.js"></script>
   <script type="module" src="/js/bedside/index.js"></script>
   <script defer src="/js/learningHub.js"></script>
   <script defer src="/js/admin.js?v=7.1.3"></script>
diff --git a/public/js/calculators.js b/public/js/calculators.js
index 07f474f..7af2296 100644
--- a/public/js/calculators.js
+++ b/public/js/calculators.js
@@ -1,7 +1,12 @@
+import { parseAgeMonths, formatParsedAge } from './calculators/age.js';
+import { initImageLightbox } from './calculators/lightbox.js';
+
 // ============================================================
 // CALCULATORS.JS — Pediatric clinical calculators
 // ============================================================
 
+initImageLightbox();
+
 (function() {
   var _inited = false;
   document.addEventListener('tabChanged', function(e) {
@@ -10,49 +15,6 @@
     initCalculators();
   });
 
-  // ── Flexible age parser ─────────────────────────────────────────────
-  // Accepts: "3y", "3 years", "29m", "29 months", "2y5m", "2 years 5 months",
-  //          "15d", "15 days", "3y 2m 10d", "36" (months), "3.5 years", etc.
-  // Returns age in months (may be fractional), or null if unparseable.
-  function parseAgeMonths(input) {
-    if (input == null) return null;
-    var s = String(input).toLowerCase().trim();
-    if (!s) return null;
-    // Plain number with no unit: if >= 24 assume years, else months. Matches
-    // common shorthand ("36" for 3y, "6" for 6 months).
-    if (/^[\d.]+$/.test(s)) {
-      var n = parseFloat(s);
-      if (isNaN(n)) return null;
-      return n >= 24 ? n : n; // keep as months; user can add unit if they meant years
-    }
-    var total = 0;
-    var matched = false;
-    // Use (?![a-z]) instead of \b so "2y5m" terminates "y" correctly.
-    // Order matters: longest-first alternations (years before yrs before y, etc.).
-    var my = s.match(/([\d.]+)\s*(?:years|year|yrs|yr|y)(?![a-z])/);
-    if (my) { total += parseFloat(my[1]) * 12; matched = true; }
-    var mm = s.match(/([\d.]+)\s*(?:months|month|mos|mo|m)(?![a-z])/);
-    if (mm) { total += parseFloat(mm[1]); matched = true; }
-    var mw = s.match(/([\d.]+)\s*(?:weeks|week|wks|wk|w)(?![a-z])/);
-    if (mw) { total += parseFloat(mw[1]) * 7 / 30.4375; matched = true; }
-    var md = s.match(/([\d.]+)\s*(?:days|day|d)(?![a-z])/);
-    if (md) { total += parseFloat(md[1]) / 30.4375; matched = true; }
-    return matched ? total : null;
-  }
-
-  function formatParsedAge(months) {
-    if (months < 1) {
-      var d = Math.round(months * 30.4375);
-      return '= ' + d + ' day' + (d === 1 ? '' : 's') + ' (' + months.toFixed(2) + ' mo)';
-    }
-    if (months < 24) {
-      return '= ' + (Math.round(months * 10) / 10) + ' months';
-    }
-    var yr = Math.floor(months / 12);
-    var mo = Math.round(months - yr * 12);
-    if (mo === 12) { yr += 1; mo = 0; }
-    return '= ' + yr + ' yr' + (mo ? ' ' + mo + ' mo' : '') + ' (' + Math.round(months) + ' mo total)';
-  }
   // Expose for debugging / other modules
   window._parseAgeMonths = parseAgeMonths;
 
@@ -2899,43 +2861,3 @@
     resultDiv.innerHTML = html;
   }
 })();
-
-// ============================================================
-// IMAGE LIGHTBOX — any element with data-img-src opens fullscreen
-// ============================================================
-(function() {
-  document.addEventListener('click', function(e) {
-    var opener = e.target.closest && e.target.closest('[data-img-src]');
-    if (opener) {
-      e.preventDefault();
-      var lb = document.getElementById('img-lightbox');
-      if (!lb) return;
-      var src = opener.dataset.imgSrc;
-      var title = opener.dataset.imgTitle || '';
-      document.getElementById('img-lightbox-img').src = src;
-      document.getElementById('img-lightbox-img').alt = title;
-      document.getElementById('img-lightbox-title').textContent = title;
-      document.getElementById('img-lightbox-open').href = src;
-      lb.style.display = 'flex';
-      return;
-    }
-    // Close on close button, on backdrop click (not on image), and on Escape (below)
-    var closeBtn = e.target.closest && e.target.closest('#img-lightbox-close');
-    var lb2 = document.getElementById('img-lightbox');
-    if (!lb2 || lb2.style.display !== 'flex') return;
-    if (closeBtn || e.target === lb2) {
-      lb2.style.display = 'none';
-      document.getElementById('img-lightbox-img').src = '';
-    }
-  });
-  document.addEventListener('keydown', function(e) {
-    if (e.key === 'Escape') {
-      var lb = document.getElementById('img-lightbox');
-      if (lb && lb.style.display === 'flex') {
-        lb.style.display = 'none';
-        document.getElementById('img-lightbox-img').src = '';
-      }
-    }
-  });
-})();
-
diff --git a/public/js/calculators/age.js b/public/js/calculators/age.js
new file mode 100644
index 0000000..fea0498
--- /dev/null
+++ b/public/js/calculators/age.js
@@ -0,0 +1,36 @@
+export function parseAgeMonths(input) {
+  if (input == null) return null;
+  var s = String(input).toLowerCase().trim();
+  if (!s) return null;
+  // Plain number with no unit: keep as months; user can add a unit if they meant years.
+  if (/^[\d.]+$/.test(s)) {
+    var n = parseFloat(s);
+    if (isNaN(n)) return null;
+    return n;
+  }
+  var total = 0;
+  var matched = false;
+  var my = s.match(/([\d.]+)\s*(?:years|year|yrs|yr|y)(?![a-z])/);
+  if (my) { total += parseFloat(my[1]) * 12; matched = true; }
+  var mm = s.match(/([\d.]+)\s*(?:months|month|mos|mo|m)(?![a-z])/);
+  if (mm) { total += parseFloat(mm[1]); matched = true; }
+  var mw = s.match(/([\d.]+)\s*(?:weeks|week|wks|wk|w)(?![a-z])/);
+  if (mw) { total += parseFloat(mw[1]) * 7 / 30.4375; matched = true; }
+  var md = s.match(/([\d.]+)\s*(?:days|day|d)(?![a-z])/);
+  if (md) { total += parseFloat(md[1]) / 30.4375; matched = true; }
+  return matched ? total : null;
+}
+
+export function formatParsedAge(months) {
+  if (months < 1) {
+    var d = Math.round(months * 30.4375);
+    return '= ' + d + ' day' + (d === 1 ? '' : 's') + ' (' + months.toFixed(2) + ' mo)';
+  }
+  if (months < 24) {
+    return '= ' + (Math.round(months * 10) / 10) + ' months';
+  }
+  var yr = Math.floor(months / 12);
+  var mo = Math.round(months - yr * 12);
+  if (mo === 12) { yr += 1; mo = 0; }
+  return '= ' + yr + ' yr' + (mo ? ' ' + mo + ' mo' : '') + ' (' + Math.round(months) + ' mo total)';
+}
diff --git a/public/js/calculators/lightbox.js b/public/js/calculators/lightbox.js
new file mode 100644
index 0000000..581056a
--- /dev/null
+++ b/public/js/calculators/lightbox.js
@@ -0,0 +1,35 @@
+export function initImageLightbox() {
+  document.addEventListener('click', function(e) {
+    var opener = e.target.closest && e.target.closest('[data-img-src]');
+    if (opener) {
+      e.preventDefault();
+      var lb = document.getElementById('img-lightbox');
+      if (!lb) return;
+      var src = opener.dataset.imgSrc;
+      var title = opener.dataset.imgTitle || '';
+      document.getElementById('img-lightbox-img').src = src;
+      document.getElementById('img-lightbox-img').alt = title;
+      document.getElementById('img-lightbox-title').textContent = title;
+      document.getElementById('img-lightbox-open').href = src;
+      lb.style.display = 'flex';
+      return;
+    }
+    var closeBtn = e.target.closest && e.target.closest('#img-lightbox-close');
+    var lb2 = document.getElementById('img-lightbox');
+    if (!lb2 || lb2.style.display !== 'flex') return;
+    if (closeBtn || e.target === lb2) {
+      lb2.style.display = 'none';
+      document.getElementById('img-lightbox-img').src = '';
+    }
+  });
+
+  document.addEventListener('keydown', function(e) {
+    if (e.key === 'Escape') {
+      var lb = document.getElementById('img-lightbox');
+      if (lb && lb.style.display === 'flex') {
+        lb.style.display = 'none';
+        document.getElementById('img-lightbox-img').src = '';
+      }
+    }
+  });
+}