To check an image’s dimensions, right-click it and choose Properties, then Details, on Windows. On a Mac, open it in Preview and press Command + I. On a phone, open the photo’s info panel. Or upload it to a free image inspector.
Some of the most common questions people type into Google are small and practical. “What size is this image?” “How long should my title be?” “How do I use a schema generator?” They sound basic, but they cover three of the most important on-page SEO factors: page speed, click-through rate and how well search engines understand your content.
This guide answers all three with step-by-step instructions for every device, plus the reasoning that experienced SEO professionals use.
Part 1: How to Check the Dimensions of an Image
Image dimensions are the width and height in pixels, for example 1920 × 1080. File size is how much storage the image uses, for example 240 KB. Both matter for website speed.
On Windows
- Right-click the image file and select Properties.
- Open the Details tab.
- Look under Image for Dimensions, Width and Height.
Shortcut: in File Explorer, switch to the Details view and add the “Dimensions” column, or hover over the file to see a tooltip.
On a Mac
- Open the image in Preview.
- Choose Tools → Show Inspector, or press Command + I.
- The General tab shows the pixel dimensions and DPI.
In Finder, you can also select the file, press Command + I and check the “More Info” section.
On iPhone and iPad
Open the photo in the Photos app and swipe up, or tap the info (i) button. Recent versions of iOS show the resolution in megapixels and pixel dimensions, plus the file size.
On Android
In Google Photos, open the image and swipe up, or tap the three-dot menu and then Details. You will see the resolution in megapixels and pixel dimensions.
In a web browser
Right-click an image on a web page and choose Open image in new tab. Many browsers show the dimensions in the tab title. Developers can right-click and choose Inspect to compare the rendered size with the intrinsic (natural) size, which quickly reveals oversized images.
The fastest option: a free online image inspector
Upload any image to our Image Inspector to see pixel dimensions, file size, format and aspect ratio in seconds. The file never leaves your browser.
What size should website images be?
| Image use | Typical dimensions | Target file size |
|---|---|---|
| Full-width hero | 1920 × 1080 px (16:9) | Under 200–300 KB |
| Blog featured image | 1200 × 675 px (16:9) | Under 150 KB |
| Open Graph social image | 1200 × 630 px | Under 300 KB |
| Content image | 800–1200 px wide | Under 100–150 KB |
| Thumbnail | 300–400 px wide | Under 40 KB |
| Favicon | 512 × 512 px source, multiple sizes output | Very small |
Use modern formats such as WebP or AVIF, always set width and height attributes to prevent layout shift, and lazy-load images below the fold. These three habits fix most image-related Core Web Vitals problems.
Part 2: What Is the Ideal Length of a Title Tag?
Google truncates titles based on pixel width (roughly 600 pixels on desktop), not a strict character count. In practice, most titles of 50–60 characters display in full. Wide letters such as “W” and “M” use more space than narrow ones such as “i” and “l”.
Title tag best practices
- Put the primary keyword near the start.
- Make every title unique across your site.
- Write for clicks: clear benefit, specific promise, honest wording.
- Add your brand at the end if space allows, for example “| Brand”.
- Avoid keyword stuffing. Google often rewrites titles that look spammy or do not match the page.
Meta descriptions and other length limits
| Element | Recommended length |
|---|---|
| Title tag | 50–60 characters (about 600 px) |
| Meta description | About 140–160 characters |
| URL slug | 3–6 meaningful words, hyphenated |
| H1 heading | Clear and descriptive; usually under 70 characters |
| Image alt text | A short, accurate description, usually under 125 characters |
Test pixel width and character count with our Meta Length Checker, generate tags with the Meta Tag Generator, and create clean URLs with the Slug Generator.
A title tag is an advert in the search results. Moving from position 5 to position 3 is hard; improving click-through rate at position 5 with a better title is often easy.
Part 3: How to Use a Schema Generator
Schema markup (structured data) is code that tells search engines and AI systems exactly what your content is: an organisation, a local business, a product, an article, an event or a person. Google recommends the JSON-LD format.
Step-by-step
- Choose the schema type that matches the page: Organization or LocalBusiness for your homepage, Article or BlogPosting for posts, Product for product pages, Event for events, FAQPage for genuine FAQ content.
- Open a schema generator such as our free Schema Generator.
- Fill in accurate details that match visible page content: name, URL, logo, address, phone, opening hours, prices and so on.
- Copy the JSON-LD code.
- Add it to the page, either in the head section, through an SEO plugin, or in a Custom HTML block in WordPress.
- Validate with Google’s Rich Results Test and the Schema.org validator.
- Monitor the Enhancements reports in Google Search Console.
A local bakery adds LocalBusiness schema with its address, phone, opening hours, price range and geo-coordinates, matching the details on its Google Business Profile. The markup does not guarantee a ranking boost, but it removes ambiguity about who the business is and where it operates. That helps search engines and AI assistants present the bakery accurately.
What schema can and cannot do in 2026
- Schema helps understanding and eligibility for rich results. It does not guarantee them.
- Google limited FAQ rich results in 2023 mainly to well-known, authoritative government and health websites, and deprecated HowTo rich results. FAQ markup still helps machines understand Q&A content.
- Markup must match visible content. Hidden or misleading markup can lead to manual actions.
- Structured, entity-rich content is increasingly useful for AI answer engines, which rely on clear facts and relationships.
Schema does not make a weak page strong. It makes a strong page unambiguous, and unambiguous pages are the ones machines are happy to quote.
Use Cases
- Bloggers resizing images and polishing titles before publishing.
- Ecommerce stores adding Product schema with price and availability.
- Local businesses adding LocalBusiness schema and fixing slow hero images.
- Agencies running quick on-page audits for new clients.
- Multilingual sites pairing schema with correct hreflang tags (try our hreflang generator).
Comparison: Manual vs Plugin vs Generator
| Method | Pros | Cons |
|---|---|---|
| Write JSON-LD by hand | Full control and precision | Easy to make syntax mistakes |
| SEO plugin | Automatic, site-wide basics | Generic; may not cover special types well |
| Schema generator | Fast, guided, valid syntax | Copy-paste needed; update when details change |
Your Pre-Publish On-Page SEO Checklist
Run through this checklist before publishing any page or blog post.
- Images: resized to the display size, compressed, saved as WebP or AVIF, with descriptive file names and accurate alt text.
- Width and height attributes set on every image to prevent layout shift.
- Title tag: unique, 50–60 characters, primary keyword near the start.
- Meta description: 140–160 characters with a clear benefit and call to action.
- One H1 that matches the page’s main topic, with logical H2 and H3 sections below it.
- Short, readable URL slug with the main keyword.
- Internal links to related pages and from relevant existing pages to the new page.
- Schema markup for the page type, validated without errors.
- An answer-first introduction that answers the main question in two or three sentences.
- Mobile check on a real phone for readability and tap targets.
Common Mistakes to Avoid
- Uploading photos straight from a camera or phone. A 4000-pixel, 5 MB photo displayed at 800 pixels wastes bandwidth and slows the page.
- Relying on CSS to shrink images. The browser still downloads the full-size file.
- Using the same title on many pages. Duplicate titles confuse search engines and searchers.
- Stuffing keywords into alt text. Alt text is for accessibility first. Describe the image honestly.
- Copying schema from another site. Markup must describe your page and match what users can see.
- Never re-validating schema. Changes to prices, hours or addresses must be reflected in your markup too.
Future Trends in On-Page SEO
- AI Overviews and answer engines reward clear structure, concise answers and well-defined entities.
- Image search and visual AI (such as Google Lens) make descriptive file names, alt text and image quality more valuable.
- Performance budgets are becoming standard, with strict limits on page and image weight.
- Automated SEO QA tools check titles, image sizes and schema on every publish.
Key Terms Explained
- Pixel dimensions: the width and height of an image in pixels, such as 1200 × 675.
- Aspect ratio: the proportion of width to height, such as 16:9 or 1:1.
- Intrinsic size vs rendered size: the image file’s real size versus the size it is displayed at on the page.
- Title tag: the HTML title shown in browser tabs and usually as the clickable headline in search results.
- JSON-LD: the structured data format recommended by Google, placed in a script tag.
- Rich results: enhanced search listings such as product prices, review stars or event dates.
Conclusion: Small Fixes, Big SEO Gains
Knowing how to check the dimensions of an image, the right title tag length and how to use a schema generator gives you three of the fastest on-page SEO wins available. Lighter images make pages faster, better titles earn more clicks, and valid schema makes your content unambiguous to search engines and AI. Make them part of your publishing checklist and every new page starts stronger.
Which Sources Back This Guide?
We checked the rules, rates and figures in this guide against the official and primary sources below. Fees, thresholds and platform features change, so confirm current details at the source before you act.
- Google Search Central: title links: how Google chooses and displays titles.
- Google Search Central: intro to structured data: how schema markup works.
- Google Search Central: image SEO best practices: image formats, alt text and sizing.
- Schema.org validator: check any structured data.
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