How to validate user input in Bubble

The simplest and most reliable way to validate user input in Bubble is to use the element’s built‑in “This input should not be empty” and “Content format” options, combined with Conditions and workflow actions that only run when the input is valid. Bubble will automatically block the workflow and show the red outline if validation fails.

Core Ways to Validate Input

Bubble gives you several real, built‑in mechanisms to validate data before allowing a workflow to continue. You can combine them for strong validation.

• Input properties: In the Input element, enable This input should not be empty. Bubble prevents workflow triggers when it’s empty.
• Content format: Set the input’s type (email, number, text) so Bubble enforces correct formatting automatically.
• Conditionals: Use the input’s “Invalid” state to show error messages when user‑typed data doesn’t meet rules.
• Workflow conditions: Add “Only when” to workflow actions so they run only if the input is valid.
• Regex checks: Use “Extract with Regex” for custom rules (e.g., password strength).

Example: Validating an Email Input

This shows the pattern you’ll use for nearly all validation in Bubble.

• Set the Input’s Content format to Email. Bubble will check email structure automatically.
• Enable This input should not be empty.
• Create a Text element that’s visible only when Input Email is invalid.
• In your “Sign up” workflow, add an Only when: Input Email’s value is valid.

// Example condition in a workflow action
Only when: Input Email's value:extract with Regex is not empty  // custom rule if needed

Example: Validating Password Strength

• Create an Input for password (Type: password).
• Add a text warning visible when a regex fails.

// Example regex check for minimum 8 chars and 1 number
Only when: Input Password's value:extract with Regex ([A-Za-z0-9]{8,}) is not empty

Server-side Validation

Before saving data in a backend workflow, add “Only when” rules to double‑check everything. Frontend validation prevents user mistakes, but backend validation protects your database.