Ever published a blog post packed with stunning images, only to wonder why it’s not ranking? Here’s the truth: those beautiful visuals might be invisible to Google. The culprit? Missing or poorly written alt tags.
If you’re scratching your head wondering what are alt tags and why everyone keeps saying they’re important for SEO, you’re in the right place. Let’s break down everything you need to know about alt tags, from the basics to advanced optimization techniques that’ll help your blog posts climb those search rankings.
What Are Alt Tags Anyway?
Alt tags (technically called “alt attributes” or “alt text”) are short text descriptions you add to images in your HTML code. They tell search engines and screen readers what’s in your image when it can’t be displayed or seen.
Think of alt tags as the backup plan for your images. When a photo fails to load, that descriptive text pops up instead. More importantly, they’re how visually impaired users experience your images through screen readers, and how Google “sees” your pictures.
Here’s what an alt tag looks like in HTML:
<img src="chocolate-cake-recipe.jpg" alt="homemade chocolate cake with fudge frosting on white plate">The Technical Breakdown
Alt tags serve three primary functions in web development:
- Accessibility: Screen readers read alt text aloud to visually impaired users
- SEO: Search engines use alt text to understand and index your images
- Fallback: Displays when images fail to load due to slow connections or broken links
According to recent data, websites with properly optimized image alt text see up to 35% better rankings in image search results (citation needed). That’s a massive opportunity most bloggers are leaving on the table.
Why Alt Tags Matter More Than You Think
You might be thinking, “It’s just a description of an image. How important can it be?” Pretty darn important, actually.
Accessibility Is Non-Negotiable
First things first: accessibility isn’t optional. About 2.2 billion people worldwide have some form of vision impairment. When you skip alt tags, you’re literally making your content inaccessible to millions of potential readers.
Screen readers rely on alt text to describe images to users who can’t see them. Without alt tags, these users just hear “image” or get complete silence. Not exactly a great user experience, right?
Google Can’t See Your Images (Without Your Help)
Here’s the kicker: Google’s pretty smart, but it can’t fully “see” images the way humans do. Sure, Google’s AI has gotten better at image recognition, but it still relies heavily on alt text to understand context, relevance, and how your images relate to your content.
When you add descriptive, keyword-rich alt tags, you’re essentially giving Google a roadmap to your visual content. This helps with:
- Better rankings in Google Images
- Improved overall page SEO
- Higher chances of appearing in visual search results
- Enhanced topical relevance signals
The SEO Benefits You’re Missing Out On
Let’s talk about the money side of things. Proper alt tag optimization isn’t just good practice—it’s a legitimate traffic driver.
Image Search Traffic Is Real Traffic
Google Images accounts for roughly 22% of all web searches (citation needed). That’s not trivial. Every image on your blog is a potential entry point for new readers. But only if Google can find and understand those images through properly written alt text.
I’ve seen blogs increase their organic traffic by 15-30% simply by going back and adding optimized alt tags to existing content. That’s low-hanging fruit you can’t afford to ignore.
Alt Tags Boost Page Relevance
Search engines use alt text as context clues to understand what your entire page is about. When your alt tags align with your target keywords and content topics, it reinforces your page’s relevance for those search terms.
Think of it this way: if you’re writing about “easy vegan recipes,” and all your image alt tags mention specific vegan dishes, ingredients, and cooking methods, Google gets a crystal-clear picture of your content’s focus.
They Improve User Experience Signals
When images fail to load (which happens more than you’d think, especially on mobile devices), descriptive alt text maintains the user experience. Visitors can still understand what they’re missing, which means:
- Lower bounce rates
- Better engagement metrics
- More time on page
- Improved user satisfaction scores
All of these signal to Google that your content deserves to rank higher.
How to Write Alt Tags That Actually Work
Okay, enough theory. Let’s get practical. Writing effective alt tags isn’t rocket science, but there’s definitely a right and wrong way to do it.
Be Specific and Descriptive
Generic alt text like “image123” or “photo” is useless. You want to paint a picture with words (pun intended). Describe what’s actually in the image as if you’re explaining it to someone over the phone.
Bad: “cake” Better: “chocolate cake” Best: “three-layer chocolate cake with cream cheese frosting and raspberry garnish”
Include Your Target Keywords (Naturally)
Yes, you should include relevant keywords in your alt tags, but—and this is crucial—only when it makes sense. Keyword stuffing is obvious, annoying, and can actually hurt your SEO.
Keyword stuffing (DON’T do this): “best chocolate cake recipe easy chocolate cake homemade chocolate cake”Natural keyword use: “homemade chocolate layer cake from easy recipe”
Keep It Concise
Screen readers typically cut off alt text around 125 characters, and Google recommends keeping it even shorter. Aim for one or two descriptive sentences maximum. Get straight to the point.
Don’t Start With “Image of” or “Picture of”
Screen readers already announce that it’s an image. Starting your alt text with “image of” is redundant and wastes valuable character space.
Unnecessary: “image of a golden retriever puppy playing in grass” Better: “golden retriever puppy playing in grass”
Context Matters
Your alt text should relate to the surrounding content. An image of a laptop could be described dozens of different ways depending on the article context:
- In a tech review: “Dell XPS 13 laptop open on desk showing screen display”
- In a remote work article: “professional working on laptop from home office”
- In a productivity post: “laptop with productivity apps open on screen”
Common Alt Tag Mistakes Killing Your Rankings
Even bloggers who know about alt tags often mess them up. Let’s address the biggest mistakes I see all the time.
Leaving Alt Tags Empty
This is mistake number one. Empty alt attributes look like this: alt="". While this is technically valid HTML (and actually recommended for purely decorative images), you should never leave alt tags empty on meaningful content images.
Using the File Name
Your camera spits out images named “IMG_2847.jpg.” That’s not a useful alt tag. Many content management systems will auto-populate the alt field with the file name if you don’t provide one. Always, always replace it with actual descriptive text.
Writing Alt Tags for Every Single Image
Plot twist: not every image needs alt text. Decorative images—things like design elements, spacers, or purely aesthetic graphics that add no information—should have empty alt attributes (alt=""). This tells screen readers to skip them.
Making Alt Text Too Long
I mentioned this earlier, but it bears repeating. Rambling, paragraph-long alt text is bad for everyone. Screen reader users get frustrated, and search engines might truncate or devalue it.
Duplicating Alt Text
If you have multiple images on a page, each one needs unique alt text. Copy-pasting the same description isn’t helpful and can look like spam to search engines.
Alt Tags vs. Image Titles: What’s the Difference?
This confuses a lot of people, so let’s clear it up.
Alt tags (alt attribute) are for accessibility and SEO. They describe what’s in the image for screen readers and search engines.
Image titles (title attribute) create a tooltip when someone hovers over an image with their mouse. They’re optional and less important for SEO.
File names are what you name your image file before uploading. They do matter for SEO and should be descriptive (use hyphens, not underscores).
Here’s the pecking order of importance:
- Alt tags (most important)
- File names (important)
- Image titles (nice to have)
- Captions (important for user experience, less so for SEO)
Focus your energy on getting alt tags right first, then optimize the others.
Tools to Make Alt Tag Creation Effortless
Look, I get it. Going through every image on your blog and writing custom alt text is time-consuming. Thankfully, there are tools that can help.
Most content management systems make adding alt text pretty straightforward:
- WordPress: Edit any image and you’ll see an “Alternative Text” field
- Squarespace: Click an image, select “Edit,” and find the “Alt Text” option
- Wix: Click an image, go to settings, and add alt text there
But if you want to take it to the next level, you need specialized tools.
At Write-Click Media, we use AltText.ai on all our sites to create perfect alt tags that help rank our articles. This AI-powered tool analyzes your images and generates SEO-optimized, contextually relevant alt text in seconds. It’s been a game-changer for our workflow, saving hours while ensuring every single image is properly optimized for both accessibility and search rankings. The best part? It understands context, so the alt text it generates actually makes sense for your specific content and target keywords.
FAQ: Your Alt Tag Questions Answered
Do alt tags really help with SEO?
Absolutely. Alt tags help search engines understand your images, improve your chances of ranking in image search, and contribute to overall page relevance. They’re also essential for accessibility, which is increasingly important for SEO.
How long should alt text be?
Aim for 125 characters or less, but focus on being descriptive rather than hitting a specific length. One or two concise sentences usually does the trick.
Should I use keywords in every alt tag?
Only when it’s natural and relevant. Your primary goal is to describe the image accurately. If your target keyword fits naturally into that description, great. If not, don’t force it.
What about decorative images?
Purely decorative images (like design elements or dividers) should have empty alt attributes: alt="". This tells screen readers to skip them entirely.
Can I use the same alt text for similar images?
No. Each image should have unique alt text that describes what makes it different, even if the images are similar.
Do social media posts need alt text?
Yes! Most social platforms now support alt text. Twitter, Facebook, Instagram, and LinkedIn all allow you to add alt text to images, improving accessibility and potentially reach.
How do I add alt text to images I’ve already published?
Go back into your content management system, edit each post, click on your images, and add alt text in the appropriate field. Then update/republish the post.
Will Google penalize me for missing alt tags?
Google won’t directly penalize you, but you’ll miss out on ranking opportunities and fail to meet accessibility standards, which can indirectly hurt your SEO.
Wrap Up: Alt Tags Are Your Secret Weapon
Here’s the bottom line: what are alt tags? They’re one of the simplest, most effective SEO optimizations you can implement today. They improve accessibility, help Google understand your content, drive image search traffic, and take just a few seconds per image to add.
Every image on your blog is an opportunity to reinforce your content’s relevance and reach a wider audience. Don’t waste that opportunity.
Start with your most important blog posts—your cornerstone content and top traffic drivers. Add thoughtful, descriptive alt text to every meaningful image. Then make it a habit to add alt tags as you publish new content going forward.
Trust me, your SEO rankings (and your visually impaired readers) will thank you.
Ready to optimize your blog images? Go audit your top 5 blog posts right now and add alt tags where they’re missing. Your future traffic is waiting.