How to validate a form field for a barcode format like ABCD0312

Need to lock down your input to a strict barcode format like ABCD0312? This guide shows how to create a validation rule that ensures: The first 4 characters are uppercase letters (A–Z) and the last 4 characters are digits (0–9)

🔧 What we're validating

We want the field (e.g. Barcode) to only be marked as valid when it matches this structure:

✅ Validation Rule Setup

In the Field Validation Rules tab:

Mark form as Valid without message when:

This regex means:

• ^[A-Z]{4} → Starts with 4 capital letters

• [0-9]{4}$ → Ends with 4 digits

• ^...$ → Anchors it to exactly 8 characters, no more, no less

❌ Mark form as Invalid

Use a fallback “Otherwise” condition to catch anything that doesn’t match:

This always evaluates as true, meaning any unmatched input is invalid by default.

🧪 Test Examples