Real-World Example: Custom T-Shirt Shop

Let me walk you through a COMPLETE, realistic example from start to finish. You’re selling custom t-shirts and need dynamic pricing based on style, size, print type, quantity, and add-ons. Here’s exactly how to set it up:

📋 STEP 1: Basic Info Tab

Calculator Name: Custom T-Shirt Price Calculator
Description: Configure your custom t-shirt and get an instant price quote
Assignment Strategy: Category Calculator
Select Categories: Check “Custom T-Shirts” and “Apparel”

🎨 STEP 2: Fields Tab – Create Your Input Fields

Click “Add Field” for each one and configure like this:

Field #1: T-Shirt Style (Dropdown)

Field Type: Dropdown
Label: “Choose Your T-Shirt Style”
Field Key: tshirt_style
Required: Yes
Options:
- Basic Cotton (value: basic, price: 0) – This is our base
- Premium Soft Blend (value: premium, price: 5)
- Vintage Distressed (value: vintage, price: 8)

Field #2: Size (Dropdown)

Field Type: Dropdown
Label: “Select Size”
Field Key: size
Required: Yes
Options:
- Small (value: s, price: 0)
- Medium (value: m, price: 0)
- Large (value: l, price: 0)
- XL (value: xl, price: 2)
- 2XL (value: 2xl, price: 4)
- 3XL (value: 3xl, price: 6)

Field #3: Print Type (Radio Buttons)

Field Type: Radio Buttons
Label: “Choose Print Method”
Field Key: print_type
Required: Yes
Options:
- Screen Print (value: screen, price: 0) – Standard option
- Direct-to-Garment (value: dtg, price: 3) – Better quality
- Vinyl Heat Transfer (value: vinyl, price: 5) – Premium option

Field #4: Quantity (Number Input)

Field Type: Number Input
Label: “How Many T-Shirts?”
Field Key: quantity
Required: Yes
Min Value: 1
Max Value: 500
Default Value: 1
Price Per Unit: 0 (we’ll handle quantity in the formula)

Field #5: Rush Order (Checkbox)

Field Type: Checkbox
Label: “Rush Order (2-Day Production)”
Field Key: rush_order
Required: No
Price if Checked: 15

Field #6: Gift Packaging (Checkbox)

Field Type: Checkbox
Label: “Add Gift Packaging”
Field Key: gift_packaging
Required: No
Price if Checked: 5

Field #7: Design File (File Upload)

Field Type: File Upload
Label: “Upload Your Design (PNG, JPG, PDF)”
Field Key: design_file
Required: Yes
Allowed File Types: .png, .jpg, .jpeg, .pdf, .ai
Max File Size: 10MB

Field #8: Special Instructions (Text Area)

Field Type: Text Area
Label: “Any Special Instructions? (Optional)”
Field Key: special_notes
Required: No
Max Length: 500 characters

💰 STEP 3: Formula Tab – Set Up Your Pricing Logic

This is where the magic happens! Here’s how to configure the formula:

Base Price:

$15 (This is the starting price for a basic t-shirt with screen print)

Base Price:

Enter: $15

Formula:

Enter this formula using basic math operators (+, -, *, /):

(15 + tshirt_style + size + print_type + rush_order + gift_packaging) * quantity

🧮 How The Formula Works:

The formula uses your field keys directly to reference their values. Just type the field key name as-is — no special characters needed. Here’s what each part means:

15 = Base price for any t-shirt
tshirt_style = Adds $0 for Basic, $5 for Premium, or $8 for Vintage
size = Adds $0 for S/M/L, $2 for XL, $4 for 2XL, $6 for 3XL
print_type = Adds $0 for Screen, $3 for DTG, or $5 for Vinyl
rush_order = Adds $15 if checked, $0 if not checked
gift_packaging = Adds $5 if checked, $0 if not checked
quantity = The number customer enters (multiplies the whole total)

📊 Example Calculation:

Customer orders: Premium Soft Blend, XL, DTG Print, Quantity 3, with Rush Order

(15 + 5 + 2 + 3 + 15 + 0) * 3
= 40 * 3
= $120 TOTAL

Breakdown:

15 = base price
5 = premium t-shirt
2 = XL size
3 = DTG print
15 = rush order
0 = no gift packaging
× 3 = quantity of 3 shirts

💡 Formula Tips:

Use field keys directly in your formula — just type the key name as-is (e.g. quantity, not {quantity})
Field keys must match EXACTLY what you set in the Fields tab (case-sensitive!)
You can use: + (add), – (subtract), * (multiply), / (divide)
Use parentheses () to control order of operations
Checkboxes return their price value if checked, 0 if unchecked
Number fields return whatever number the customer enters

⚙️ STEP 4: Settings Tab

Status: Active
Priority: 1 (default is fine unless you have multiple calculators)
Hide Quantity Selector: Yes (because we’re handling quantity in our calculator)

💾 STEP 5: Save & Assign

Click “Save Calculator”
Since we chose “Category Calculator” in Step 1, it’s already assigned to your Custom T-Shirts category
Go to any product in that category and boom – your calculator is live!

✅ STEP 6: Don’t Forget!

Remember the TWO critical requirements from the Common Issues section:

Your calculator HAS fields (we added 8!) ✅
Your WooCommerce product MUST have a base price set (go to each product and set regular price to any number like $10 – the calculator will replace it) ✅

🎉 Result:

Your customers now see a beautiful, modern calculator that walks them through choosing their t-shirt style, size, print method, and quantity. The price updates in real-time as they make selections. When they hit “Add to Cart”, the custom price and ALL their selections are saved with the order!