diff --git a/app/util/validator.py b/app/util/validator.py
new file mode 100644
index 0000000..a6d84ff
--- /dev/null
+++ b/app/util/validator.py
@@ -0,0 +1,18 @@
+#!/usr/bin/env python3.11
+from app.util.globals import Error
+
+def validateInputData(inputFileDir: str) -> Error:
+  with open(inputFileDir, newline='') as csvfile:
+    includes = ['Pupil #', 'CrsNo', 'Description', 'Alternate?']
+    data = csvfile.readline().replace('\n', '').split(',')
+    missing = [e for e in includes if e not in data]
+    if len(missing) > 0:
+      description = 'You are missing the following: '
+      for i in range(len(missing)):
+        if i != len(missing) - 1: description += f'{missing[i]}, '
+        else: description += f'{missing[i]}'
+      missingErr = Error('Missing Required Fields', description)
+
+      return missingErr
+    
+  return None
diff --git a/main.py b/main.py
index 7cbe5cd..00dcef1 100755
--- a/main.py
+++ b/main.py
@@ -9,6 +9,7 @@ from app.util.globals import Error
 from app.util.courses import getCourses, writeCoursesToCSV
 from app.util.students import getStudents, writeStudentsToCSV
 from app.util.errorCalculator import writeErrorsToCSV
+from app.util.validator import validateInputData
 
 eel.init('template')
   
@@ -49,6 +50,10 @@ def start(
   block_class_limit = int(block_class_limit)
   total_blocks      = int(total_blocks)
 
+  eel.post_data('Validating input file...')
+  validateErr = validateInputData(raw_data_dir)
+  if validateErr is not None: return validateErr.__dict__
+
   # call pre-algorithm functions read raw data into a processable format
   eel.post_data('Collecting student information...')
   students = getStudents(