Free Alt Text Checker

Getting a complete alt text audit with this tool is fast, straightforward, and requires no technical expertise. Follow these steps to get the most out of the Alt Text Checker:

• Step 1 — Input Your URL or HTML: Enter the full URL of the webpage you want to audit (e.g., https://www.yoursite.com/about) into the input field, or paste your raw HTML source code directly into the HTML editor. The tool supports both live websites and static HTML snippets, making it equally useful for production sites and development environments.
• Step 2 — Run the Analysis: Click the "Check Alt Text" button to initiate the scan. The tool will fetch the page content, parse all <img> elements, extract their alt, src, and title attributes, and process them through its evaluation engine.
• Step 3 — Review the Results: The results panel displays a structured table listing every image found on the page. Each row shows the image source URL, a thumbnail preview (when available), the current alt text value, and a status indicator — Pass, Warning, or Fail — based on alt text quality criteria.
• Step 4 — Interpret the Status Flags:
  • Fail (Missing): The alt attribute is completely absent from the <img> tag. This is a critical error for both SEO and accessibility.
  • Fail (Empty on Content Image): The alt attribute is present but empty on an image that appears to convey meaningful information.
  • Warning (Generic): The alt text contains placeholder text like "image," "photo," or filenames like "IMG_1234.jpg," which provide no semantic value.
  • Warning (Too Long): The alt text exceeds the recommended 125-character limit, which may cause screen readers to truncate the description.
  • Pass: The alt text is present, descriptive, and within an optimal length range.
• Step 5 — Export and Fix: Use the export feature to download a CSV report of all findings. Take the report to your CMS or codebase, prioritize fixing all Fail statuses first, then address Warnings to maximize the overall impact on your SEO and accessibility scores.

For best results, run the Alt Text Checker on every key page of your website — homepage, product pages, blog posts, and landing pages — and schedule periodic re-audits after any significant content update.

The Alt Text Checker is a powerful, free online tool designed to analyze and audit the alternative text (alt text) attributes of images across any webpage or HTML document. It systematically scans your content, identifies every <img> tag, and evaluates whether each image has a meaningful, descriptive, and SEO-optimized alt attribute. Whether you're a web developer validating a new build, an SEO specialist auditing an existing site, or a digital accessibility advocate ensuring WCAG compliance, the Alt Text Checker provides a comprehensive, actionable report in seconds. The tool goes beyond simple presence detection — it evaluates the quality of your alt text, flagging images with missing attributes, empty alt tags, generic placeholder text, and overly long descriptions that may harm user experience. By consolidating all image alt text data into a single, easy-to-read interface, this tool eliminates the need for manual code inspection and empowers website owners to make data-driven improvements that simultaneously boost search engine rankings and digital accessibility.

Alt text sits at the critical intersection of SEO performance and web accessibility, making it one of the most impactful yet frequently overlooked elements of any website. Here's why regularly checking and optimizing your alt text is non-negotiable for any serious web presence:

• Search Engine Indexing: Search engine crawlers like Googlebot cannot "see" images the way humans do. Alt text is the primary mechanism by which crawlers understand an image's context, subject matter, and relevance. Well-crafted alt text ensures your images appear in Google Image Search, driving an additional channel of organic traffic directly to your pages.
• WCAG and ADA Compliance: The Web Content Accessibility Guidelines (WCAG 2.1, Success Criterion 1.1.1) mandate that all non-decorative images must have a text alternative. Missing or inadequate alt text can expose businesses to legal liability under the Americans with Disabilities Act (ADA) and similar regulations worldwide, particularly as web accessibility lawsuits continue to rise.
• Screen Reader Compatibility: Over 7.6 million people in the United States alone live with visual impairments and rely on screen readers like JAWS, NVDA, or VoiceOver. These assistive technologies read alt text aloud, allowing users to understand image content. Missing alt text renders those images completely invisible to this audience, creating a fundamentally broken user experience.
• Core Web Vitals and User Experience: When images fail to load due to slow connections or server errors, alt text is displayed in place of the image. Descriptive alt text preserves the communicative intent of the page, ensuring users still receive the information they need regardless of technical failures.
• Keyword Relevance Signals: Strategically incorporating target keywords into alt text provides additional on-page relevance signals to search engines without keyword stuffing in body copy, contributing to higher rankings for competitive search terms.

Using the Alt Text Checker regularly — especially after publishing new content or updating your image library — is a best practice that ensures your site never inadvertently loses accessibility compliance or SEO equity.

Writing effective alt text is both an art and a science. Following these industry-proven best practices will help you craft alt attributes that satisfy both search engines and accessibility standards simultaneously:

• Be Concise and Descriptive: Aim for alt text between 50 and 125 characters. It should describe the image's content and function accurately without being unnecessarily verbose. Think of it as a caption written for someone who cannot see the image.
• Incorporate Target Keywords Naturally: Where contextually appropriate and accurate, include your primary or secondary target keyword within the alt text. However, never force a keyword where it does not belong — keyword-stuffed alt text is a spam signal that can harm your rankings.
• Describe Function Over Appearance for Clickable Images: For clickable images (like buttons or linked images), the alt text should describe the action or destination rather than the visual appearance. For example, instead of alt="magnifying glass icon", use alt="Search products".
• Use Empty Alt Text for Decorative Images: Purely decorative images — such as background patterns, dividers, or aesthetic stock photos — should use an empty alt attribute (alt=""). This signals to screen readers that the image is presentational and can be safely skipped.
• Avoid Starting with "Image of" or "Picture of": Screen readers already announce that an element is an image, so beginning your alt text with these phrases is redundant and wastes your character budget. Start directly with the descriptive content.
• Provide Context from the Surrounding Content: The best alt text accounts for the image's context on the page. Always write alt text that aligns with the surrounding text and the overall page topic.
• Never Use Raw Filenames as Alt Text: Filenames like DSC_00423_final_v2.jpg provide zero accessibility or SEO value. Always replace auto-generated filenames with human-readable, keyword-relevant descriptions.
• Audit Regularly: Alt text optimization is not a one-time task. Every time new images are added — through blog posts, product updates, or template changes — new audit cycles are necessary. Use the Alt Text Checker on a recurring schedule to maintain continuous compliance.

Even experienced web professionals make alt text mistakes that silently erode SEO rankings and accessibility scores. Here are the most prevalent errors to actively avoid:

• Completely Omitting the Alt Attribute: The most common and damaging mistake is forgetting to add an alt attribute at all. An <img> tag without any alt attribute is treated as an accessibility failure under WCAG 2.1 and is effectively ignored by search engines for indexing purposes.
• Using Vague, Generic Descriptions: Writing alt text like alt="image", alt="photo", or alt="banner" conveys no meaningful information about the image's actual content or context, contributing nothing to either SEO relevance signals or the experience of screen reader users.
• Keyword Stuffing in Alt Attributes: Attempting to cram multiple keywords into every alt attribute — e.g., alt="cheap flights book flights airline tickets best flight deals" — is recognized and penalized by search engine spam-detection algorithms. It also actively degrades the experience for visually impaired users who must listen to a string of disconnected keywords read aloud.
• Duplicating Surrounding Caption Text Verbatim: If an image already has a visible caption that fully describes it, using the identical text in the alt attribute creates a repetitive, disruptive experience for screen reader users who will hear the same description twice in rapid succession.
• Ignoring Complex Images Like Charts and Infographics: Writing alt="sales chart" for a complex data visualization is insufficient. The correct approach is to provide a brief alt attribute and a full text alternative in the page body (e.g., a data table) referenced via aria-describedby.
• Applying the Same Alt Text to Multiple Different Images: Using identical alt text for different images — a common shortcut in CMS environments with auto-populated fields — causes confusion for both search engines and screen reader users. Each image is unique and deserves a unique, contextually appropriate description.