Date

The date field collects one calendar date and stores it as a YYYY-MM-DD string.

Validation

Fillo checks both the string shape and the calendar itself, so a value like 2026-02-30 is rejected. The stored answer has no time or timezone.

There's no minimum-date, maximum-date, disabled-day, or display-format option in the current schema. If you need those rules, use a custom field and validate the value in the component and your receiving system.

Add a date field

In the dashboard, select Add block and choose Date.

const startDateField = {
  id: "start_date",
  kind: "date",
  label: "Preferred start date",
  required: true,
} as const;

URL prefill accepts the same YYYY-MM-DD value through the field ID, for example ?start_date=2026-08-01.

Related

• Prefill and hidden fields: Seed a date from a query string or app state.
• Custom: Add date-range rules the built-in field doesn't expose.
• Schema and validation: Keep response validation consistent across client and server.