Item logo image for FormBoundary — Form Validation Checker

FormBoundary — Form Validation Checker

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Overview

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.

Details

  • Version
    0.2.1
  • Updated
    August 8, 2026
  • Features
    Offers in-app purchases
  • Offered by
    kmin
  • Size
    47.31KiB
  • Languages
    English
  • Developer
    王开民
    华龙苑北里 昌平区, 北京市 102200 CN
    Email
    wkm534470831@gmail.com
    Phone
    +86 133 1134 1578
  • Trader
    This developer has identified itself as a trader per the definition from the European Union and committed to only offer products or services that comply with EU laws.

Privacy

Manage extensions and learn how they're being used in your organization

FormBoundary — Form Validation Checker has disclosed the following information regarding the collection and usage of your data. More detailed information can be found in the developer's privacy policy.

FormBoundary — Form Validation Checker handles the following:

Web history
Website content

This developer declares that your data is

  • Not being sold to third parties, outside of the approved use cases
  • Not being used or transferred for purposes that are unrelated to the item's core functionality
  • Not being used or transferred to determine creditworthiness or for lending purposes

Support

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