Jess's Calendar Colorizer
a tool by Jessica Eastman Stewart

Jess's Calendar Colorizer

Set your rules once. Your Google Calendar auto-colors itself every 5 minutes — no manual work needed.

1
Calendar
2
Rules
3
Script
4
Install
Which calendar do you want to color-code?
Enter your calendar name exactly as it appears in Google Calendar's left sidebar.
This is usually your email address for your main calendar. Check the left sidebar in Google Calendar if you're not sure.
The script will also color-code future events up to 90 days ahead.
Define your color rules
If an event title or description contains your keyword, it gets that color. Rules apply in order — first match wins.
No rules yet — add your first one below.
Add a rule
Keyword or phrase
Match in
Assign this Google Calendar color
Pick a color above, then click Add.
Rules are case-insensitive. Add as many as you need.
Your custom Apps Script
This complete script was built from your rules. Copy it, then follow the install steps.
✓ Script generated with color rule(s). Ready to copy! 

      
    


    

      
      
    

  


  
  

    
Install in about 5 minutes

    
No coding required — just paste and click. Your calendar will start auto-coloring within minutes.


    
    
      
  1. 
        
    
          Go to script.google.com and sign in with the same Google account as your calendar.
        
    
      
    2. 
      
  2. 
        
    
          Click New project in the top-left corner. A blank script editor will open.
        
    
      
    3. 
      
  3. 
        
    
          Select all the placeholder code in the editor (Ctrl+A or Cmd+A) and delete it.
        
    
      
    4. 
      
  4. 
        
    
          Paste your copied script (Ctrl+V or Cmd+V).
        
    
      
    5. 
      
  5. 
        
    
          Click the 💾 Save icon (or Ctrl+S). Name the project something like Calendar Color Coder.
        
    
      
    6. 
      
  6. 
        
    
          Click ▶ Run to test it once manually. Google will ask for permissions — click Review Permissions → Allow. Then check your calendar to confirm the colors applied.
        
    
      
    7. 
      
  7. 
        
    
          Set up the automatic trigger: Click the ⏰ Triggers icon (alarm clock) in the left sidebar, then + Add Trigger.
          

    
          Configure it like this:
    
          • Function: colorCodeCalendar
    
          • Event source: Time-driven
    
          • Type: Minutes timer
    
          • Interval: Every 5 minutes
          

    
          Click Save.
        
    
      
    8. 
      
  8. 
        
    
          Done! Your calendar will now automatically apply your color rules every 5 minutes — including new events as they're added.
        
    
      
    9. 
    


    


    

      Troubleshooting tips

      • Colors not showing? Double-check that your calendar name matches exactly (it's case-sensitive).

      • "Authorization required" error? Click Run again and re-approve permissions.

      • To update your rules, edit the script and save — the trigger will pick up the changes automatically.

      • You can pause auto-coloring anytime by deleting the trigger in the Triggers panel.