# Validation Modes
Canonical URL: https://monetly.io/docs/validation-modes
Last updated: 2026-06-18
Audience: Monetly users and AI assistants helping users operate Monetly
Status: Public usage documentation, non-authoritative
## Summary
A validation mode controls what kind of behavior the experiment asks visitors to show.

The right mode depends on the commitment you want to test. Use the lightest mode that still answers your product question.
## Key Rules
- Waitlist mode measures signup intent.
- Fake door mode measures stronger interest before a real product exists.
- Payment intent mode measures checkout-level commitment without taking real payment.
- Do not switch modes mid-experiment unless you are intentionally starting a new validation cycle.

## Common Mistakes
- Using waitlist mode when the real question is willingness to pay.
- Using payment intent mode before the offer and price are clear.
- Comparing results across modes as if they measured the same behavior.

## Waitlist
Use waitlist mode when you want to measure whether visitors are willing to leave contact information for the idea.

This is useful for early interest checks, but it is a lighter signal than purchase intent.

## Fake Door
Use fake door mode when you want visitors to move toward an action that looks like product access or purchase intent, while clearly avoiding real fulfillment.

This mode is useful when a signup alone is too weak to answer the product question.

## Payment Intent
Use payment intent mode when the key question is whether visitors are willing to reach a checkout-level commitment.

Monetly does not process real payment in this mode. The point is to measure behavior around the commitment boundary.
## Related Pages
- [Create Your First Experiment](https://monetly.io/docs/create-your-first-experiment.md)
- [Traffic and Ads](https://monetly.io/docs/traffic-and-ads.md)
- [Understanding Decisions](https://monetly.io/docs/understanding-decisions.md)