About this tool
Free Image Size & Dimensions Checker
Use this free Image Size & Dimensions Checker to inspect the technical details of a JPG, PNG, or WebP file before uploading, publishing, printing, resizing, or compressing it. Select an image and the tool immediately reports its width and height in pixels, file size, format, simplified aspect ratio, megapixel count, orientation, total pixel count, and whether transparent pixels are present. Image dimensions describe the number of pixels across the width and height of a file. A 1920 × 1080 image, for example, contains 1920 horizontal pixels and 1080 vertical pixels. Dimensions affect how much visual detail an image can hold and whether it meets the minimum or exact requirements of a website, marketplace, application form, content-management system, or social platform. File size is different from image dimensions. Two images can have the same width and height but very different sizes in KB or MB because format, compression level, image detail, and metadata also affect storage. Checking both measurements helps you diagnose why an upload is rejected. If the dimensions are wrong, use an image resizer. If the pixel dimensions are acceptable but the file is too large, use an image compressor. The aspect ratio expresses the relationship between width and height in its simplest whole-number form. Common examples include 1:1 for a square, 4:3 for traditional displays and photographs, 3:2 for many cameras, and 16:9 for widescreen images. The orientation result identifies the file as landscape, portrait, or square, making it easier to confirm whether the image suits its intended layout. Megapixels are calculated by multiplying width by height and dividing by one million. This measurement describes pixel count, not guaranteed visual quality. Sharpness also depends on focus, lighting, compression, editing, and the original source. A larger megapixel value does not automatically mean that an image is better for every use. Transparency detection is useful when preparing logos, icons, graphics, and product cutouts. PNG and WebP can contain transparent or partially transparent pixels, while JPG does not support transparency. The checker examines the decoded pixels in your browser and reports whether transparency is present; it does not alter the original file. All inspection happens locally on your device. The selected image is not uploaded to WebToolsEdge, and no converted copy is created. Once you know the current properties, you can crop unwanted edges, resize to exact dimensions, or compress to a specific KB limit using the related image tools.
If the reported width or height does not meet your destination's requirements, continue with the Image Resizer to Exact Dimensions. When the dimensions are correct but the file exceeds an upload limit, use the Image Compressor to Specific KB. You can also browse all Image Tools.
Step by step
How to use Image Size & Dimensions Checker
- 1
Choose a JPG, PNG, or WebP image up to 25 MB.
- 2
Wait briefly while the browser reads the file and inspects its pixels.
- 3
Review the width, height, file size, format, aspect ratio, megapixels, orientation, and transparency result.
- 4
Use the copy button to copy a plain-text summary of the image details.
- 5
Choose another image to inspect a different file, or clear the current result.
Highlights
Image Size & Dimensions Checker features
Image width and height in pixels
File size in KB or MB
JPG, PNG, and WebP format identification
Simplified aspect-ratio calculation
Megapixel and total-pixel count
Landscape, portrait, or square orientation
Transparent-pixel detection
Copyable image-detail summary
Private browser-based inspection without upload
Questions
Image Size & Dimensions Checker FAQ
How do I check the dimensions of an image online?+
Choose a JPG, PNG, or WebP file. The checker reads it locally and displays its width and height in pixels.
What is the difference between image dimensions and file size?+
Dimensions measure width and height in pixels. File size measures how much storage the encoded file uses in KB or MB.
Can I check an image aspect ratio?+
Yes. The tool reduces the width and height to a simplified ratio such as 1:1, 4:3, 3:2, or 16:9.
How are image megapixels calculated?+
Megapixels equal width multiplied by height, divided by one million. They describe pixel count rather than guaranteed image quality.
Can the checker detect transparent images?+
Yes. It examines decoded PNG and WebP pixels for full or partial transparency. JPG files are reported as non-transparent because the format does not support alpha transparency.
Does this tool change or compress my image?+
No. It only reads and reports image properties. The original file remains unchanged.
Which image formats are supported?+
The checker supports JPG and JPEG, PNG, and WebP images up to 25 MB.
What does image orientation mean?+
Landscape means the width is greater than the height, portrait means the height is greater, and square means both dimensions are equal.
Is my image uploaded to a server?+
No. File reading, previewing, measurement, and transparency detection happen locally in your browser.
What should I do if my image dimensions or file size are wrong?+
Use the Image Resizer to Exact Dimensions when width or height is wrong, or the Image Compressor to Specific KB when the file exceeds an upload-size limit.