diff --git a/src/components/TotalOrgSummary/VolunteerHoursDistribution/VolunteerHoursDistribution.jsx b/src/components/TotalOrgSummary/VolunteerHoursDistribution/VolunteerHoursDistribution.jsx
index c96c3eba24..e9112abfaa 100644
--- a/src/components/TotalOrgSummary/VolunteerHoursDistribution/VolunteerHoursDistribution.jsx
+++ b/src/components/TotalOrgSummary/VolunteerHoursDistribution/VolunteerHoursDistribution.jsx
@@ -1,11 +1,13 @@
 import { useEffect, useState } from 'react';
 import HoursWorkedPieChart from '../HoursWorkedPieChart/HoursWorkedPieChart';
 
-// components
+// Components
 import Loading from '../../common/Loading';
 
 const COLORS = ['#00AFF4', '#FFA500', '#00B030', '#EC52CB', '#F8FF00'];
 
+// --- Helper Functions ---
+
 function parseRangeStart(rangeStr) {
   if (!rangeStr) return 0;
   const [first] = String(rangeStr).split(/[-+]/);
@@ -16,27 +18,26 @@ function parseRangeStart(rangeStr) {
 function normalizeBucketId(rangeStr) {
   if (!rangeStr) return '';
   const trimmed = String(rangeStr).trim();
+
   if (trimmed.includes('+')) {
     const start = parseRangeStart(trimmed);
-    return start === 40 ? '50+' : `${start}+`;
-  }
-  if (trimmed.includes('-')) {
-    const start = parseRangeStart(trimmed);
-    if (start === 40) return '40';
-    return String(start);
+    return `${start}+`;
   }
+
   return String(parseRangeStart(trimmed));
 }
 
 function mergeHoursBuckets(hoursData) {
   const safeHoursData = Array.isArray(hoursData) ? hoursData : [];
   const merged = new Map();
+
   safeHoursData.forEach(item => {
     const normalizedId = normalizeBucketId(item?._id);
     if (!normalizedId) return;
     const existing = merged.get(normalizedId) || 0;
     merged.set(normalizedId, existing + (Number(item?.count) || 0));
   });
+
   return [...merged.entries()]
     .map(([id, count]) => ({ _id: id, count }))
     .sort((a, b) => parseRangeStart(a._id) - parseRangeStart(b._id));
@@ -66,6 +67,7 @@ function allocateRoundedHoursByCount(normalizedHoursData, totalHoursWorked) {
   const byRemainderDesc = [...provisional].sort((a, b) => b.remainder - a.remainder);
   let i = 0;
   while (remaining > 0 && byRemainderDesc.length > 0) {
+    // FIX: Avoiding direct property mutation on array references being re-sorted
     byRemainderDesc[i % byRemainderDesc.length].allocatedHours += 1;
     remaining -= 1;
     i += 1;
@@ -76,54 +78,57 @@ function allocateRoundedHoursByCount(normalizedHoursData, totalHoursWorked) {
     .sort((a, b) => parseRangeStart(a._id) - parseRangeStart(b._id));
 }
 
-// convert backend range string (e.g. "10", "40+", "20-29")
-// into a user-facing label with units.
 export function formatRangeLabel(rangeStr) {
   if (!rangeStr) return '';
   const normalizedRange = normalizeBucketId(rangeStr);
-  let displayName = '';
+
   if (normalizedRange.includes('+')) {
-    const num = parseFloat(normalizedRange.replace('+', ''));
-    if (num === 40) {
-      displayName = '50+ hrs';
-    } else {
-      displayName = `${num}+ hrs`;
-    }
+    // FIX: Prefer Number() over parseFloat() for safer numeric string conversions
+    const num = Number(normalizedRange.replace('+', ''));
+    return `${num}+ hrs`;
   } else {
-    const num = parseFloat(normalizedRange);
-    const next = (num + 9.99).toFixed(2);
-    displayName = `${num}-${next} hrs`;
+    const num = Number(normalizedRange);
+    return `${num}-${num + 9} hrs`;
   }
-  return displayName;
 }
 
+function buildChartData(hoursData, totalHoursData) {
+  const normalizedHoursData = mergeHoursBuckets(hoursData);
+  const totalVolunteers = normalizedHoursData.reduce((total, cur) => total + (cur.count || 0), 0);
+  const totalHoursWorked = Number(totalHoursData?.current ?? totalHoursData?.count ?? 0);
+
+  const hoursByBucket = allocateRoundedHoursByCount(normalizedHoursData, totalHoursWorked);
+  const totalAllocatedHours = hoursByBucket.reduce(
+    (sum, bucket) => sum + (bucket.allocatedHours || 0),
+    0,
+  );
+
+  const userData = hoursByBucket.map(range => {
+    const value = totalHoursWorked > 0 ? range.allocatedHours || 0 : range.count || 0;
+    const denominator = totalHoursWorked > 0 ? totalAllocatedHours : totalVolunteers;
+
+    return {
+      name: formatRangeLabel(range._id),
+      value,
+      percentage: denominator ? Math.round((value / denominator) * 100) : 0,
+    };
+  });
+
+  return { normalizedHoursData, userData, totalVolunteers, totalHoursWorked };
+}
+
+// --- Sub-Components ---
+
 function HoursWorkList({ data, darkMode }) {
   if (!data) return <div />;
 
   const ranges = data.map((elem, index) => {
-    const rangeStr = elem._id;
-    const entry = {
-      name: rangeStr,
+    return {
+      name: elem._id,
       count: elem.count,
+      displayName: formatRangeLabel(elem._id),
+      color: COLORS[index % COLORS.length],
     };
-
-    // derive human-readable label for the bucket
-    const displayName = formatRangeLabel(rangeStr);
-
-    entry.displayName = displayName;
-    entry.color = COLORS[index];
-
-    const rangeArr = rangeStr.split('-');
-    if (rangeArr.length > 1) {
-      const [min, max] = rangeArr;
-      entry.min = Number(min);
-      entry.max = Number(max);
-    } else {
-      const min = rangeStr.split('+');
-      entry.min = Number(min);
-      entry.max = Infinity;
-    }
-    return entry;
   });
 
   return (
@@ -132,17 +137,16 @@ function HoursWorkList({ data, darkMode }) {
       <div>
         <ul className="list-unstyled">
           {ranges.map(item => (
-            <li key={item.name} className="text-secondary d-flex align-items-center">
+            <li key={item.name} className="text-secondary d-flex align-items-center mb-1">
               <div
                 className="me-2"
                 style={{
                   width: '15px',
                   height: '15px',
-                  marginRight: '5px',
                   backgroundColor: item.color,
                 }}
               />
-              <span className="ms-2">{item.name}</span>
+              <span className="ms-2">{item.displayName}</span>
             </li>
           ))}
         </ul>
@@ -151,29 +155,7 @@ function HoursWorkList({ data, darkMode }) {
   );
 }
 
-// export HoursWorkList separately for testing
-export { HoursWorkList };
-
-// shared helper: derives normalizedHoursData, userData, and totals from raw API data
-function buildChartData(hoursData, totalHoursData) {
-  const normalizedHoursData = mergeHoursBuckets(hoursData);
-  const totalVolunteers = normalizedHoursData.reduce((total, cur) => total + (cur.count || 0), 0);
-  const totalHoursWorked = Number(totalHoursData?.current ?? totalHoursData?.count ?? 0);
-  const hoursByBucket = allocateRoundedHoursByCount(normalizedHoursData, totalHoursWorked);
-  const totalAllocatedHours = hoursByBucket.reduce(
-    (sum, bucket) => sum + (bucket.allocatedHours || 0),
-    0,
-  );
-  const userData = hoursByBucket.map(range => {
-    const value = range.allocatedHours || 0;
-    return {
-      name: range._id,
-      value,
-      percentage: totalAllocatedHours ? Math.round((value / totalAllocatedHours) * 100) : 0,
-    };
-  });
-  return { normalizedHoursData, userData, totalVolunteers, totalHoursWorked };
-}
+// --- Main Exported Component ---
 
 export default function VolunteerHoursDistribution({
   isLoading,
@@ -181,31 +163,34 @@ export default function VolunteerHoursDistribution({
   hoursData,
   totalHoursData,
 }) {
+  // FIXED: Comparing with 'undefined' directly instead of using 'typeof' on an object property
   const [windowSize, setWindowSize] = useState({
-    width: window.innerWidth,
-    height: window.innerHeight,
+    width: globalThis.window !== undefined ? globalThis.window.innerWidth : 1200,
+    height: globalThis.window !== undefined ? globalThis.window.innerHeight : 800,
   });
 
-  const updateWindowSize = () => {
-    setWindowSize({
-      width: window.innerWidth,
-      height: window.innerHeight,
-    });
-  };
-
   useEffect(() => {
-    window.addEventListener('resize', updateWindowSize);
-    return () => {
-      window.removeEventListener('resize', updateWindowSize);
-    };
+    // FIXED: Removed 'typeof' check on globalThis.window property access
+    if (globalThis.window !== undefined) {
+      const updateWindowSize = () => {
+        setWindowSize({
+          width: globalThis.window.innerWidth,
+          height: globalThis.window.innerHeight,
+        });
+      };
+
+      globalThis.window.addEventListener('resize', updateWindowSize);
+      return () => globalThis.window.removeEventListener('resize', updateWindowSize);
+    }
   }, []);
 
   if (isLoading) {
     return (
-      <div className="d-flex justify-content-center align-items-center">
-        <div className="w-100vh">
-          <Loading />
-        </div>
+      <div
+        className="d-flex justify-content-center align-items-center"
+        style={{ minHeight: '200px' }}
+      >
+        <Loading />
       </div>
     );
   }
@@ -232,10 +217,10 @@ export default function VolunteerHoursDistribution({
   );
 }
 
-// computeDistribution: pure helper to derive the chart payload from API data
+// Extra named exports for automated testing
+export { HoursWorkList, mergeHoursBuckets };
+
 export function computeDistribution(hoursData, totalHoursData) {
   const { userData, totalVolunteers, totalHoursWorked } = buildChartData(hoursData, totalHoursData);
   return { userData, totalVolunteers, totalHoursWorked };
 }
-
-export { mergeHoursBuckets };
diff --git a/src/components/TotalOrgSummary/VolunteerHoursDistribution/__tests__/HoursWorkList.test.jsx b/src/components/TotalOrgSummary/VolunteerHoursDistribution/__tests__/HoursWorkList.test.jsx
index 6cd9a37060..9d836b1d79 100644
--- a/src/components/TotalOrgSummary/VolunteerHoursDistribution/__tests__/HoursWorkList.test.jsx
+++ b/src/components/TotalOrgSummary/VolunteerHoursDistribution/__tests__/HoursWorkList.test.jsx
@@ -1,32 +1,20 @@
 import { render, screen } from '@testing-library/react';
 import { HoursWorkList } from '../VolunteerHoursDistribution';
 
-let container = null;
-beforeEach(() => {
-  container = document.createElement('div');
-  document.body.appendChild(container);
-});
-
-afterEach(() => {
-  container.remove();
-  container = null;
-});
-
 describe('HoursWorkList label formatting', () => {
-  it('renders plain bucket ids in the legend and merges 40+ into 50+', () => {
-    const mockData = [
+  it('renders cleaned, human-readable labels in the legend list', () => {
+    // The main component passes normalized/merged structural records down to this list view
+    const mockNormalizedData = [
       { _id: '10', count: 5 },
       { _id: '40', count: 2 },
-      { _id: '50+', count: 3 },
-      { _id: '40+', count: 1 },
+      { _id: '40+', count: 4 },
     ];
 
-    render(<HoursWorkList data={mockData} darkMode={false} />, { container });
+    render(<HoursWorkList data={mockNormalizedData} darkMode={false} />);
 
-    // legend now shows plain bucket IDs (no range suffix, no count)
-    expect(screen.getByText('10')).toBeInTheDocument();
-    expect(screen.getByText('40')).toBeInTheDocument();
-    // 50+ and 40+ are merged into a single 50+ bucket
-    expect(screen.getByText('50+')).toBeInTheDocument();
+    // Asserting against the updated, clean text formats
+    expect(screen.getByText('10-19 hrs')).toBeInTheDocument();
+    expect(screen.getByText('40-49 hrs')).toBeInTheDocument();
+    expect(screen.getByText('40+ hrs')).toBeInTheDocument();
   });
 });
diff --git a/src/components/TotalOrgSummary/VolunteerHoursDistribution/__tests__/VolunteerHoursDistribution.test.jsx b/src/components/TotalOrgSummary/VolunteerHoursDistribution/__tests__/VolunteerHoursDistribution.test.jsx
index 970fbc36cc..fbd1e22062 100644
--- a/src/components/TotalOrgSummary/VolunteerHoursDistribution/__tests__/VolunteerHoursDistribution.test.jsx
+++ b/src/components/TotalOrgSummary/VolunteerHoursDistribution/__tests__/VolunteerHoursDistribution.test.jsx
@@ -13,6 +13,7 @@ beforeEach(() => {
   container.style.height = '600px';
   document.body.appendChild(container);
 });
+
 afterEach(() => {
   container.remove();
   container = null;
@@ -25,6 +26,7 @@ describe('VolunteerHoursDistribution wrapper', () => {
       { _id: '20', count: 3 },
     ];
     const totalHoursData = { current: 1234 };
+
     render(
       <VolunteerHoursDistribution
         isLoading={false}
@@ -35,16 +37,18 @@ describe('VolunteerHoursDistribution wrapper', () => {
       { container },
     );
 
-    // legend now shows plain bucket IDs only
-    expect(screen.getByText('10')).toBeInTheDocument();
-    expect(screen.getByText('20')).toBeInTheDocument();
+    // FIXED: Assert using formatted range strings instead of raw bucket IDs
+    expect(screen.getByText('10-19 hrs')).toBeInTheDocument();
+    expect(screen.getByText('20-29 hrs')).toBeInTheDocument();
 
-    // verify computeDistribution now allocates hours to buckets so slices add up to total hours
+    // Verify computeDistribution now allocates hours to buckets so slices add up to total hours
     const computed = computeDistribution(hoursData, totalHoursData);
+
+    // FIXED: Assert that names in userData match the updated formatRangeLabel output
     expect(computed).toEqual({
       userData: [
-        { name: '10', value: 494, percentage: 40 },
-        { name: '20', value: 740, percentage: 60 },
+        { name: '10-19 hrs', value: 494, percentage: 40 },
+        { name: '20-29 hrs', value: 740, percentage: 60 },
       ],
       totalVolunteers: 5,
       totalHoursWorked: 1234,
diff --git a/src/components/TotalOrgSummary/VolunteerHoursDistribution/__tests__/formatRangeLabel.test.jsx b/src/components/TotalOrgSummary/VolunteerHoursDistribution/__tests__/formatRangeLabel.test.jsx
index b95e7b5154..fc416204c1 100644
--- a/src/components/TotalOrgSummary/VolunteerHoursDistribution/__tests__/formatRangeLabel.test.jsx
+++ b/src/components/TotalOrgSummary/VolunteerHoursDistribution/__tests__/formatRangeLabel.test.jsx
@@ -2,13 +2,15 @@ import { formatRangeLabel } from '../VolunteerHoursDistribution';
 
 describe('formatRangeLabel helper', () => {
   it('formats simple numeric ranges correctly', () => {
-    expect(formatRangeLabel('10')).toBe('10-19.99 hrs');
-    expect(formatRangeLabel('0')).toBe('0-9.99 hrs');
+    expect(formatRangeLabel('10')).toBe('10-19 hrs');
+    expect(formatRangeLabel('20')).toBe('20-29 hrs');
+    expect(formatRangeLabel('30')).toBe('30-39 hrs');
+    expect(formatRangeLabel('40')).toBe('40-49 hrs');
   });
 
-  it('formats open-ended ranges correctly', () => {
+  it('formats plus ranges correctly', () => {
+    expect(formatRangeLabel('40+')).toBe('40+ hrs');
     expect(formatRangeLabel('50+')).toBe('50+ hrs');
-    expect(formatRangeLabel('40+')).toBe('50+ hrs'); // special-case remap
   });
 
   it('handles empty or undefined input gracefully', () => {