ARIA Attribute Validator - Online Check HTML Accessibility
Paste an HTML snippet and check for common ARIA mistakes: missing labels, invalid roles, and aria‑hidden misuse. Educate your team.
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<label>, <fieldset>, <legend>, and proper input types (email, tel, date) that convey meaning to browsers and assistive technologies. Screen readers announce these semantics, helping users understand the form's structure. Semantic HTML also enables better autofill behavior, mobile keyboard optimization, and improved SEO.aria-required="true" for required fields, aria-describedby linking inputs to help text, aria-invalid for error states, role="group" on fieldset elements, and proper aria-labelledby references. These attributes ensure screen readers provide complete context to users navigating your form.<fieldset> groups related form controls together, and <legend> provides a descriptive label for the entire group. For radio button and checkbox groups, this is essential—screen readers announce the legend before each option, helping users understand the context (e.g., "Preferred Contact Method: Email, Phone, Mail"). This builder automatically wraps grouped inputs in fieldset elements.autocomplete attribute helps browsers automatically fill in user information (names, addresses, credit card details) from saved data. For users with motor impairments or cognitive disabilities, this dramatically reduces the effort required to complete forms. WCAG 2.1 Success Criterion 1.3.5 requires identifying input purpose, and proper autocomplete values satisfy this requirement.for attribute (explicit association) links to the input's id—this is more reliable and works across all assistive technologies. Implicit association (wrapping <input> inside <label>) is simpler but less robust. This builder uses explicit for/id association, which is the W3C recommended approach for maximum compatibility.for with htmlFor and class with className. For Vue, the HTML works as-is in templates. The semantic structure remains identical across frameworks, and you can layer your framework's state management on top.Paste an HTML snippet and check for common ARIA mistakes: missing labels, invalid roles, and aria‑hidden misuse. Educate your team.
Validate a language tag like en‑US or zh‑Hans against the IANA registry. Ensure correct HTML lang attribute.
Pick a base color and generate a 10‑step scale where each step meets a specific contrast ratio against white or black. Export as CSS custom properties.
Convert plain text into HTML‑safe strings by escaping <, >, &, and quotes. Insert into code safely. Local copy.
Follow along with animated crease patterns to fold a paper crane. Pause and rewind steps.
Request HID devices and list them. Read input reports and send output. For custom hardware and controllers.
Convert English text to Braille (Grade 1 and simple Grade 2 contractions). Educational tool to understand Braille representation. Local only.
Drag colored shapes to matching outlines. Simple, no-text game for 2-4 year olds. Works on touch devices.
See how a PWA can extend content into the title bar area on desktop. Customize the window controls overlay.
Test the experimental Translation API to translate text between languages directly in the browser, without cloud calls. Check support and copy the JavaScript starter.
Paste a WebVTT file and instantly check for syntax errors. Validate timestamps and cue formatting. Essential for video devs.
Start with a base color and generate an extended palette where every shade contrasts properly with white and black. Export tokens.
Search common dream symbols and their traditional meanings. For entertainment and self-reflection. Static data.
Enter pot volume and tea type to find the right amount of dry leaf considering expansion. Avoid overflowing.
Upload any image, add a thick white border and drop shadow, and turn it into a sticker. Download as transparent PNG.
Generate a grand, aristocratic title like 'Duke of Waffleshire'. Perfect for silly fun or RPG characters. Local.
Reverse entire text, flip letters, or reverse word order. Fun for puzzles and creative writing. Instant transformation without data leaving your browser.
Convert volume and capacity units: gallon (US/UK), liter, milliliter, cup, and fluid ounce. Handy for cooking and science. Works entirely offline.
A big button that triggers a colourful confetti cannon full‑screen. Use it to celebrate small wins. Pure joy.
Draw a digit (0‑9) on the canvas and a simple neural net guess the number. Educational demo. No upload.
Fetch a site’s HSTS header and validate its syntax, max‑age, and subdomain flags. Ensure your site enforce HTTPS.
Enter any number up to trillion and get the English word representation. For filling out checks or legal documents.
Click colors on an interactive wheel and see the common emotions and meanings associated with them. A design resource.
Estimate the baby's due date based on last menstrual period (LMP) or conception date. Also shows current week and trimester. Educational only.
Play infinite sound loops of white, pink, brown, blue, and violet noise. Volume control. Help focus or mask tinnitus.
Convert carabiner strength from kN to kg/lbs and understand Major Axis vs Minor Axis markings. Quick educational reference for climbers.
Enter current weight and age to estimate adult weight based on growth curves. For purebred and mixed.
Enter original and target color to compute the exact CSS hue‑rotate(deg) filter needed. For precise icon and image tinting.
Pick colors using the HWB (Hue‑Whiteness‑Blackness) model. Get the CSS hwb() function code. Simpler than HSL for some.
Add N business days to a date, skipping weekends and optionally entering custom holidays. Regional presets.