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Input Validation Checker

Analyze HTML forms and JavaScript for proper input validation patterns. Checks for required attributes, type constraints, length limits, pattern matching, sanitization, and user error feedback.

Drop a .html or .js file here or
Well validated No validation Partial validation

How It Works

This tool parses your HTML and JavaScript to evaluate input validation quality across multiple categories. All processing happens entirely in your browser — no data is sent to any server.

Checklist Categories
  • HTML Attributes — required, type, pattern, minlength/maxlength, min/max on form inputs
  • Type Constraints — Use of semantic input types like email, number, url, tel, date instead of plain text
  • Length & Range — Enforcing minimum and maximum bounds on input values and string lengths
  • Pattern Matching — Regular expression patterns on HTML inputs and JavaScript-side regex validation
  • JS Validation — JavaScript-level checks such as trim(), type guards, empty-value checks, and form submit event handling
  • Sanitization — Input trimming, encoding, and safe DOM insertion using textContent over innerHTML
  • Error Feedback — User-visible error messages, inline validation cues, ARIA attributes for accessibility
Scoring

Each check is weighted equally. Passes score full points, warnings half, and failures zero. The final percentage determines the grade:

ScoreGrade
80 – 100%Strong input validation
50 – 79%Needs improvement
0 – 49%Weak input validation
Tip: Client-side validation improves user experience but should never be your only line of defense. Always validate on the server as well, since client-side checks can be bypassed.

Embed This Util

You can embed this util on your own site as a widget. Adding ?embed=1 to the URL loads a compact version with just the tool itself; no header, menu, or documentation. Paste this snippet into your HTML: 


    

       Copy snippet
      Adjust the height to taste.
    

  









  
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