Overview

The Enable Format Validation in Phone Inputs setting controls whether the system checks that phone numbers entered in Classter match the accepted format for the selected country. When this setting is enabled, users must enter phone numbers in a valid format that complies with international telephony standards for the country chosen in the phone field. If a number does not match the expected format, the system displays an error in real time and prevents the form from being saved until the issue is corrected.

This setting applies across key profile and admission forms, ensuring that phone data stored in the system is clean, consistently formatted, and reliable for automated communications and data quality purposes.

Setting path: Main Settings > General Settings > Basic Customization > Core Entities Settings

Type: Toggle (Enabled / Disabled)

Default value: Disabled

Applies per: Company (each institution can configure independently)

What This Setting Does

When Enabled

Phone input fields in Classter validate the entered number against internationally recognised format standards for the selected country code.

• A validation error is displayed immediately (in real time) as the user types or changes the country code, if the number does not match the expected format.
• The form cannot be saved while any required phone field contains an incorrectly formatted number.
• Validation applies to required phone fields in a blocking way (the form cannot be submitted). Optional phone fields display a real-time error indicator but do not block submission.
• The system recognises and validates the following number types per country: fixed-line, mobile, and fixed-line-or-mobile numbers.
• If the phone number is too short, too long, or otherwise does not match the selected country’s format rules, a descriptive error message is shown (for example: The number is too short, or Invalid format).

When Disabled (Default)

• Phone number fields accept any value regardless of format. No format-based validation is performed.
• Users can save forms with phone numbers that are incomplete, incorrectly formatted, or not matching the selected country’s dialling rules.
• Country codes can still be selected and displayed on phone fields (if the related country code setting is enabled — see Section 7: Notes), but no format compliance is enforced.

Where It Is Used

This setting affects phone number input fields in the following areas of the application:

Area	Who / What Is Affected
Admission Form (Advanced mode)	Data entered for the applicant (_Student_) and for any linked relatives or contacts (parents, guardians)
Quick Admission / Signup Form	Home Phone and Mobile Phone entered by the applicant during online self-registration
Guardian / Parent Fill-in Modal	Phone fields completed by parents or guardians through their dedicated contact data form
_Student_ Profile	Phone fields in the student’s contact data section
_Teacher_ Profile	Phone fields in the teacher’s additional contact data section
Relative / Contact Profiles	Phone fields on relative and contact profile forms

The setting is applied at the start of each user session and remains active across all relevant forms for the entire session.

Business Logic / Behavior 

  

 Country-Specific Validation

Phone number validation is country-specific. Each phone input field includes a country code selector. The format rules applied to the entered number are determined by the country code currently selected in that field. For example, a number entered with a UK country code must match the UK format requirements; a number with a German country code must meet German requirements, and so on.

Required Fields Only Block Submission

Phone format validation that prevents form submission only applies to phone fields that are configured as required in the relevant form. If a phone field is optional, the user may see a real-time error indicator, but will not be blocked from submitting the form. This design prevents unnecessary friction when phone data is not mandatory.

Real-Time Feedback

When this setting is enabled, the system provides real-time validation feedback. As the user types or changes the country code, the phone field is checked immediately. If the number is not valid, an error icon and a descriptive message appear next to the field without the user needing to attempt to save the form first.

 Form Submission

If a required phone field contains a number that does not match the format rules for the selected country, the form cannot be submitted. The user must correct the phone number before saving. The system highlights the problematic field and displays an appropriate error message.

K-12 vs. Higher Education Mode

The phone format validation setting behaves identically in both K-12 mode and Higher Education (College / University) mode. The validation is applied to the same form areas in both modes. There is no difference in how this feature functions depending on which education mode is active.

The only practical consideration is that in each mode, certain phone fields may be configured as required or optional differently (based on the institution’s admission form configuration). Since blocking validation only applies to required fields, the fields that actually block submission may differ between modes based on the institution’s form setup — not because of any difference in the setting’s behaviour.

Business Rule Summary

• If the setting is enabled and a phone field is required: the phone number must match the format of the selected country to save the form.
• If the setting is enabled and a phone field is optional: a real-time error indicator may appear, but the form can still be saved.
• If the setting is disabled: no format checking occurs on any phone field, required or optional.
• The setting applies per company. Different institutions in a multi-company environment can have different values.

Examples

Example 1 — Setting Enabled, Admission Form

Sunrise Academy has enabled this setting. A staff member is completing an admission form for a new applicant. The form has the Mobile Phone field marked as required. The staff member selects Germany as the country code and enters the number 123 in the Mobile Phone field. The system immediately displays an error next to the field: The number is too short. The Save button does not process the form. The staff member must enter a valid German mobile number (such as 0171 1234567 with the +49 country code pre-selected) before the form can be saved.

Example 2 — Setting Enabled, Quick Admission Signup

Valley College has enabled this setting. A prospective student is completing the online Quick Admission signup form. The Mobile Phone field is required. The student selects France as the country code and types 00000. The system shows an error instantly: Invalid number. The signup form cannot be submitted until the student provides a valid French mobile number.

Example 3 — Setting Disabled

Meadow School has this setting disabled. During Quick Admission, an applicant enters 00000 in the Home Phone field with no country code selected. The system applies no format check and accepts the entry. The record is saved with the value 00000 even though this is not a valid phone number. No error message is displayed.

When to Use

Enable This Setting When…

• Your institution wants to maintain high data quality and ensure phone numbers stored in the system are valid, correctly formatted, and usable for automated communications (such as SMS notifications, login via OTP, or automated reminders).
• You use phone-based features such as sending text messages, phone-based authentication, or any integration that relies on correctly formatted phone numbers. Incorrectly formatted numbers would cause delivery failures or integration errors.
• Your admission process requires accurate contact phone data from applicants or their relatives, and incorrect entries would cause operational problems.
• You want to reduce the risk of storing malformed or unusable phone numbers that would impact reports, exports, or third-party integrations.

Disable This Setting When…

• Your institution does not rely on automated phone-based communication, phone authentication, or integrations that require correctly formatted numbers, and data quality enforcement is not a current priority.
• You are in a data migration or transition period where users may need to enter phone numbers in non-standard formats temporarily.
• Phone fields in your system are mostly optional and not critical to your operations.
• Your user base or applicants may struggle to enter phone numbers in the validated international format, and the friction would harm the admission or registration experience.

Notes

Related Settings

Enable default country code on the phone number inputs

(Main Settings > General Settings > Basic Customization > Core Entities Settings — ID: Enable_Default_Country_Code_On_The_Phone_Number_Inputs)

This setting automatically pre-fills the country code in phone fields based on the institution’s country or the student’s/relative’s address country. When this setting is active alongside Enable Format Validation in Phone Inputs, the country code is pre-selected, and format validation then runs against that pre-selected country. It is recommended to enable both settings together for the most consistent and user-friendly experience. Without a country code, the validation engine may not be able to determine which country’s format rules to apply.

Prerequisites

• No specific prerequisite settings are required to enable this setting. It can be turned on independently.
• For the most effective and user-friendly experience, it is recommended to also enable the Enable default country code on the phone number inputs setting. Without a pre-selected country code, users must manually choose the country code for each phone field before the format can be checked.
• If enabling this setting on a system that already contains existing records: be aware that staff editing those existing records will encounter real-time format validation when a form with required phone fields is opened. If existing phone data is not in a valid international format, those forms will show errors until the phone numbers are corrected.

Additional Information

• This setting is a company-level setting. In a multi-company environment, each company / institution can configure it independently.
• The validation uses an internationally recognised phone number validation standard (ITU-T E.164 and related country-specific rules). It supports fixed-line, mobile, and fixed-line-or-mobile number types.
• This setting does not affect phone number fields in other modules that use different form rendering (such as Finance or Scheduling-specific forms). It is primarily active in Admission and Profile forms.