Search is no longer limited to text. Users search for products by photo via Google Lens, ask voice queries to Alexa, and AI assistants like ChatGPT and Perplexity can already analyze and summarize video content. In 2026, multimodal search has become a reality: search engines link text, images, audio, and video into a single system. If your content is only available in text format, you're losing traffic to competitors with video reviews and high-quality photos.

In this article, we'll cover how to prepare your site for multimodal search: from image alt texts to video transcripts and voice optimization.

What Is Multimodal Search and Why It's Changing SEO

Multimodal search is the ability of search engines to process and connect different content types: text, images, video, and audio. A user can photograph a sofa in a store and ask Google to find the same one online. Or ask Alexa: "Show me the best running headphones" — and get an answer with links to video reviews.

AI assistants now don't just read text — they analyze video and images. ChatGPT and Perplexity can extract information from video transcripts and use it in their answers. Google Lens recognizes objects in photos and uses alt texts to confirm its conclusions. You can read more about visibility in Perplexity and Google's AI Overviews in the article How to Analyze Visibility in Perplexity and SGE.

What this means for business. Your content must be available in all formats. Text on a page is no longer enough. If you have a product, you need quality photos from different angles. If you have a service, you need video reviews or tutorials. Without this, your site becomes invisible to multimodal search.

Preparing Images for Visual Search

Images are not just page decoration. They are a key element of multimodal search. AI systems recognize objects, colors, and even styles, but they need proper alt texts and quality files for accurate interpretation.

Technical requirements for images. Use modern formats — WebP or AVIF. They compress files by 25-50% without quality loss, speeding up page load. Ensure resolution is at least 1200×1200 pixels for product photos. Search engines prefer high-quality, detailed images.

What is alt text and how to write it. Alt text is a textual description of an image. In the era of multimodal search, alt texts have become critical: AI assistants use them to understand image content and cite them in their answers. The formula for good alt text: subject + action + attribute + purpose. Bad example: "Dashboard screenshot" — too generic. Good example: "Siteimprove Content Quality dashboard showing 42 readability issues across 200 blogs" — specific, with numbers and names.

What to avoid in alt texts. Don't start with phrases like "image of" or "picture of" — the system already knows it's an image. Don't use keyword stuffing — it reads as spam. Don't duplicate surrounding text word for word. Don't leave alt texts empty or auto-generated without checking — AI systems perceive this as negligence.

File names matter too. The file name is an additional signal for search engines. "walnut-dining-table.jpg" is good. "IMG_4823.jpg" is bad. Use descriptive names with hyphens. If an image carries no semantic load (background pattern, divider line), use an empty alt text: alt="". This signals the system that the image is decorative and can be ignored.

Preparing Videos for Search and AI Assistants

Video has become a full-fledged search channel. AI assistants can analyze video transcripts and use them in answers. Videos can appear in search results as separate entries, especially for "how-to" queries.

Key video metadata. The title should be descriptive, emotionally engaging, and include the keyword. Not "Video Promotion" but "10 Video Promotion Tips to Help Your Videos Rank Higher in 2026." The description should be 200-300 words explaining what the video is about. Include key phrases, timestamps for key moments, and calls to action. The thumbnail should be bright, with a close-up of a face (if applicable) or large text.

Video transcript — the most important element. A transcript is a text file containing the full transcription of the video's audio track. AI assistants can't "watch" videos, but they can read transcripts. Transcripts allow search engines and AI models to index every word spoken in the video. Place the transcript below the video on the page. This links the video to the page context and provides additional text for indexing.

Subtitles and structured data. Subtitles improve accessibility and engagement. Users are more likely to watch videos with subtitles to the end. Search engines consider watch time as a quality signal. Add VideoObject structured data to the page. This helps search engines correctly identify the video and show it in rich snippets with thumbnail, duration, and key moments. Place the video at the top of the page, "above the fold." This signals that the video is primary content.

Preparing Your Site for Voice Search

Voice search is part of the multimodal ecosystem. Users formulate queries in natural language: "Which laptop is best if I work in Photoshop?" rather than "buy laptop for design." You can learn about the ethical aspects of optimizing for neural networks in the article Ethics of Generative Optimization: Can You Negotiate with a Neural Network.

How to write for voice search. Create FAQ sections with real user questions. Answer briefly and completely — voice assistants prefer clear answers of 20-40 words. Use question phrases in H2 headings: "How to choose a laptop for graphic design?", "How long does the battery last on this model?". Structure answers in a pattern: first a direct answer, then details. The first sentence should contain the essence.

Comprehensive Multimodal Optimization Strategy

Multimodal search requires a system, not scattered actions. Here's a checklist for preparing your site.

For all pages. Ensure fast loading. LCP (Largest Contentful Paint — a metric for loading main content) should be under 2 seconds. Use modern image formats. Make sure the site is mobile-friendly.

For images. Every meaningful image should have a unique, specific alt text. The alt text should match the surrounding text and include numbers, brand names, models. File names should be descriptive. Decorative images should have an empty alt text.

For videos. Add a transcript under each video. Fill in metadata: title, description, thumbnail. Implement VideoObject structured data. Include timestamps for key moments.

For voice search. Add FAQ blocks with natural questions. Use question formulations in headings. Give a direct answer in the first sentence.

Technical foundation. Open your site to AI bots. Ensure your robots.txt file doesn't block GPTBot, PerplexityBot, and other AI crawlers. Use clean HTML without critical JavaScript blocks so bots can read content.

Conclusion

In 2026, search has become multimodal. Users search via text, photo, and voice. AI assistants analyze everything: from alt texts to video transcripts. If your content exists in only one format, you're losing customers.

Preparing your site for multimodal search involves three directions. Images: quality photos in modern formats + specific alt texts with numbers and names. Video: transcripts + filled metadata + structured data + placement "above the fold." Voice: FAQ blocks + question headings + direct answers in the first sentences.

Companies that have implemented a multimodal approach report organic traffic growth of 40-65% per year. The reason is simple: they become accessible to all types of users, regardless of how they search for information.

A professional website audit for search engines will help identify issues in preparing for multimodal search. You can comprehensively improve site visibility with the comprehensive website promotion service. Effective geo-optimization of your website is also important for local multimodal search.

Frequently Asked Questions

What is the optimal length for alt text?
Aim for 125 characters. Most screen readers pause at this length, and AI-generated short descriptions are often truncated. If you need more details, add a caption or include the information in the surrounding text.

Do I need transcripts for all videos?
Yes. A transcript is the only way for AI to index video content. Without it, the video remains a "black box" for search engines. At minimum, provide a transcript on the page.

How often should I update alt texts on old images?
Conduct an audit of your existing media library and prioritize fixes for pages with the highest traffic. You may not achieve 100% coverage immediately, but key images should be optimized first.

Does hosting choice affect multimodal search?
Yes. Server response time affects LCP — a critical ranking factor. If your hosting is slow, the page may not appear in search results, even with perfect content. For a Moscow audience, choose hosting with servers in Russia.

Is structured data for videos mandatory?
Yes, VideoObject is a required element. Without it, search engines cannot reliably identify the video on the page. It's a basic requirement for appearing in rich snippets and video search results.