Gravity Forms
+ IBAN Validator Premium

Gravity Forms IBAN Validator Premium Addon introduces enterprise-grade international bank account number validation directly into your Gravity Forms workflows. Whether collecting supplier banking details, processing European SEPA direct debits, or gathering member payout information, ensuring accurate IBAN entries before form submission is mission-critical for modern businesses.

Eliminate Costly Bounced Payments & Bank Rejection Fees

Submitting an invalid or mistyped IBAN through an online form triggers expensive operational fallout. European financial institutions, payment gateways, and clearing houses routinely charge steep return fees ($15 to $50 per failed wire or SEPA batch) when transaction data fails verification. Beyond monetary penalties, administrative teams waste hours manually contacting payees to rectify account numbers. With real-time IBAN validation, incorrect account structures are flagged and stopped the instant a user types, ensuring 100% clean banking records enter your database.

ISO 13616 Modulo-97 Real-Time Checksum Verification

Unlike superficial regex patterns that only check overall character counts, our add-on implements the authentic ISO 7064 Modulo-97 mathematical checksum algorithm specified by the ISO 13616 banking standard. Every entered IBAN is converted through standardized character-to-integer mappings and validated with high-precision arithmetic. Both browser-side JavaScript and server-side PHP engines verify that the two check digits mathematically match the country code and basic bank account number (BBAN), guaranteeing bulletproof data integrity.

Seamless User Experience with Dynamic Input Masking & Multilingual Support

IBAN strings are long and prone to manual typos when typed as a continuous string of 15 to 34 characters. The add-on features intelligent dynamic input masking that automatically formats user input into standardized 4-character blocks separated by clean spaces as they type. Furthermore, international businesses can effortlessly localize every single validation error message directly from the Gravity Forms settings panel, delivering an intuitive, localized experience for users across Germany, France, the UK, Spain, the Netherlands, and over 80 supported nations.

1. Form Initialization & Dynamic Mask Loading: When a form containing the IBAN Validator field renders, the add-on enqueues lightweight client-side input masking and validation libraries without adding bloat to unrelated pages.
2. Instant Client-Side Checksum Verification: As the respondent enters their bank account number, client-side scripts calculate the ISO 13616 Modulo-97 checksum in real-time, providing immediate visual feedback and preventing form submission if check digits fail.
3. Dual-Layer Server-Side Modulo-97 Validation: Upon form submission, the add-on sanitizes and recalculates the checksum on the WordPress server using high-precision math (with automated fallback support), safeguarding against bypassed browser validations.
4. Customizable Multilingual Error Formatting: If an invalid structure or unrecognized country code is detected, the field dynamically renders the localized error message configured in your form settings.
5. Secure Entry Storage & Workflow Handoff: Validated, clean IBAN entries are stored securely in Gravity Forms and can be seamlessly passed to payment feeds, CRM webhooks, accounting software, or automated email notifications.