FormBoundary — Form Validation Checker

Check whether HTML form constraints match client-side validation after input, change, and blur.

FormBoundary is a focused, local checker for native web-form validation. It reads validation constraints that are visible in native HTML fields, generates representative boundary values, enters one value at a time, triggers input, change, and blur events, and reports when the field's final client-side validity disagrees with the expected result derived from those constraints. Example issues it can expose: • A value allowed by HTML is rejected by JavaScript through the browser validation API. • A value outside the scanned HTML range is accepted after page logic changes or clears the constraint. • A length, range, step, required, pattern, email, date, or option case behaves differently from its declared constraint. Free includes field scanning, generated cases, single-case execution, and consistency results. Pro adds sequential batch runs, result summaries, local saved plans, reruns, and JSON/CSV reports. To request a Pro activation code, contact wkm534470831@gmail.com or WeChat kmin_w. Activation is handled manually. No price, payment link, or purchase button is shown in the extension. Privacy and safety: • Runs locally in your browser • No account or developer-operated server • No analytics or ads • Never submits forms automatically • Skips password and likely sensitive fields • Uses activeTab only after your action Important limitations: • It checks visible native input, textarea, and select fields only. • It does not click Submit or test validation that runs only in a submit handler. • It does not test server/API validation or hidden business rules. • It cannot reliably detect a visual error message unless the page also exposes the result through the field's browser validity state. • It does not support every custom component, Shadow DOM, or iframe. FormBoundary is not a complete end-to-end testing tool. It is a quick consistency check for a narrow class of client-side form-validation mistakes.