diff --git a/frontend/public/locales/en-GB/translation.json b/frontend/public/locales/en-GB/translation.json
index e4979fbbd..d29f2407b 100644
--- a/frontend/public/locales/en-GB/translation.json
+++ b/frontend/public/locales/en-GB/translation.json
@@ -1018,7 +1018,8 @@
     "title": "Remove Pages",
     "pageNumbers": {
       "label": "Pages to Remove",
-      "placeholder": "e.g., 1,3,5-8,10"
+      "placeholder": "e.g., 1,3,5-8,10",
+      "error": "Invalid page number format. Use numbers, ranges (1-5), or mathematical expressions (2n+1)"
     },
     "filenamePrefix": "pages_removed",
     "files": {
diff --git a/frontend/public/locales/en-US/translation.json b/frontend/public/locales/en-US/translation.json
index ff3ccaaf7..359b27160 100644
--- a/frontend/public/locales/en-US/translation.json
+++ b/frontend/public/locales/en-US/translation.json
@@ -747,7 +747,8 @@
     "title": "Remove Pages",
     "pageNumbers": {
       "label": "Pages to Remove",
-      "placeholder": "e.g., 1,3,5-8,10"
+      "placeholder": "e.g., 1,3,5-8,10",
+      "error": "Invalid page number format. Use numbers, ranges (1-5), or mathematical expressions (2n+1)"
     },
     "filenamePrefix": "pages_removed",
     "files": {
diff --git a/frontend/src/components/tools/removeBlanks/RemoveBlanksSettings.tsx b/frontend/src/components/tools/removeBlanks/RemoveBlanksSettings.tsx
index f40435267..0806423c5 100644
--- a/frontend/src/components/tools/removeBlanks/RemoveBlanksSettings.tsx
+++ b/frontend/src/components/tools/removeBlanks/RemoveBlanksSettings.tsx
@@ -13,7 +13,7 @@ const RemoveBlanksSettings = ({ parameters, onParameterChange, disabled = false
   const { t } = useTranslation();
 
   return (
-    <Stack gap="md">
+    <Stack gap="lg" mt="md">
       <Stack gap="xs">
         <NumberInputWithUnit
           label={t('removeBlanks.threshold.label', 'Pixel Whiteness Threshold')}
@@ -24,9 +24,6 @@ const RemoveBlanksSettings = ({ parameters, onParameterChange, disabled = false
           max={255}
           disabled={disabled}
         />
-        <Text size="xs" c="dimmed">
-          {t('removeBlanks.threshold.desc', "Threshold for determining how white a white pixel must be to be classed as 'White'. 0 = Black, 255 pure white.")}
-        </Text>
       </Stack>
 
       <Stack gap="xs">
@@ -39,9 +36,6 @@ const RemoveBlanksSettings = ({ parameters, onParameterChange, disabled = false
           max={100}
           disabled={disabled}
         />
-        <Text size="xs" c="dimmed">
-          {t('removeBlanks.whitePercent.desc', "Percent of page that must be 'white' pixels to be removed")}
-        </Text>
       </Stack>
 
       <Stack gap="xs">
@@ -52,9 +46,6 @@ const RemoveBlanksSettings = ({ parameters, onParameterChange, disabled = false
           label={
             <div>
               <Text size="sm">{t('removeBlanks.includeBlankPages.label', 'Include detected blank pages')}</Text>
-              <Text size="xs" c="dimmed">
-                {t('removeBlanks.includeBlankPages.desc', 'Include the detected blank pages as a separate PDF in the output')}
-              </Text>
             </div>
           }
         />
diff --git a/frontend/src/components/tools/removePages/RemovePagesSettings.tsx b/frontend/src/components/tools/removePages/RemovePagesSettings.tsx
index 052455f14..3ffa115d9 100644
--- a/frontend/src/components/tools/removePages/RemovePagesSettings.tsx
+++ b/frontend/src/components/tools/removePages/RemovePagesSettings.tsx
@@ -8,15 +8,41 @@ interface RemovePagesSettingsProps {
   disabled?: boolean;
 }
 
+// Validation function for page numbers (same as in parameters hook)
+const validatePageNumbers = (pageNumbers: string): boolean => {
+  if (!pageNumbers.trim()) return false;
+  
+  // Normalize input for validation: remove spaces around commas and other spaces
+  const normalized = pageNumbers.replace(/\s*,\s*/g, ',').replace(/\s+/g, '');
+  const parts = normalized.split(',');
+  
+  // Regular expressions for different page number formats
+  const singlePageRegex = /^\d+$/; // Single page: 1, 2, 3, etc.
+  const rangeRegex = /^\d+-\d*$/; // Range: 1-5, 10-, etc.
+  const negativeRegex = /^-\d+$/; // Negative: -3 (last 3 pages)
+  const mathRegex = /^\d*[n]\d*[+\-*/]\d+$/; // Mathematical: 2n+1, n-1, etc.
+  
+  return parts.every(part => {
+    if (!part) return false;
+    return singlePageRegex.test(part) || 
+           rangeRegex.test(part) || 
+           negativeRegex.test(part) || 
+           mathRegex.test(part);
+  });
+};
+
 const RemovePagesSettings = ({ parameters, onParameterChange, disabled = false }: RemovePagesSettingsProps) => {
   const { t } = useTranslation();
 
   const handlePageNumbersChange = (value: string) => {
-    // Remove spaces and normalize input
-    const normalized = value.replace(/\s+/g, '');
-    onParameterChange('pageNumbers', normalized);
+    // Allow user to type naturally - don't normalize input in real-time
+    onParameterChange('pageNumbers', value);
   };
 
+  // Check if current input is valid
+  const isValid = validatePageNumbers(parameters.pageNumbers);
+  const hasValue = parameters.pageNumbers.trim().length > 0;
+
   return (
     <Stack gap="md">
       <TextInput
@@ -26,6 +52,7 @@ const RemovePagesSettings = ({ parameters, onParameterChange, disabled = false }
         placeholder={t('removePages.pageNumbers.placeholder', 'e.g., 1,3,5-8,10')}
         disabled={disabled}
         required
+        error={hasValue && !isValid ? t('removePages.pageNumbers.error', 'Invalid page number format. Use numbers, ranges (1-5), or mathematical expressions (2n+1)') : undefined}
       />
     </Stack>
   );
diff --git a/frontend/src/hooks/tools/removePages/useRemovePagesParameters.ts b/frontend/src/hooks/tools/removePages/useRemovePagesParameters.ts
index 6a2830f2e..cdbb03eef 100644
--- a/frontend/src/hooks/tools/removePages/useRemovePagesParameters.ts
+++ b/frontend/src/hooks/tools/removePages/useRemovePagesParameters.ts
@@ -11,10 +11,33 @@ export const defaultParameters: RemovePagesParameters = {
 
 export type RemovePagesParametersHook = BaseParametersHook<RemovePagesParameters>;
 
+// Validation function for page numbers
+const validatePageNumbers = (pageNumbers: string): boolean => {
+  if (!pageNumbers.trim()) return false;
+  
+  // Normalize input for validation: remove spaces around commas and other spaces
+  const normalized = pageNumbers.replace(/\s*,\s*/g, ',').replace(/\s+/g, '');
+  const parts = normalized.split(',');
+  
+  // Regular expressions for different page number formats
+  const singlePageRegex = /^\d+$/; // Single page: 1, 2, 3, etc.
+  const rangeRegex = /^\d+-\d*$/; // Range: 1-5, 10-, etc.
+  const negativeRegex = /^-\d+$/; // Negative: -3 (last 3 pages)
+  const mathRegex = /^\d*[n]\d*[+\-*/]\d+$/; // Mathematical: 2n+1, n-1, etc.
+  
+  return parts.every(part => {
+    if (!part) return false;
+    return singlePageRegex.test(part) || 
+           rangeRegex.test(part) || 
+           negativeRegex.test(part) || 
+           mathRegex.test(part);
+  });
+};
+
 export const useRemovePagesParameters = (): RemovePagesParametersHook => {
   return useBaseParameters({
     defaultParameters,
     endpointName: 'remove-pages',
-    validateFn: (p) => p.pageNumbers.trim().length > 0,
+    validateFn: (p) => validatePageNumbers(p.pageNumbers),
   });
 };