Image Size Checker is a free online tool on YouLoveTools that tells you everything about an image file at a glance: its real format, its exact width and height in pixels, its file size, its aspect ratio, its megapixels and whether it is portrait, landscape or square. Unusually, the format is read from the file’s actual contents — its first bytes, not its name — so a file that was renamed from PNG to JPG is still identified correctly. Nothing is uploaded; the check runs in your browser.
Choose an image to check
Drag & drop here, or click to choose a file
The format shown is read from the file’s actual contents — not its name — so renamed files are still identified correctly.
Your file is processed in your browser — it is never uploaded.
Image Size & Dimension Checker — Know Your File
How to Use
- Step 1: Click the upload box or drag your image onto it.
- Step 2: Read the results table — dimensions for the form you are filling, file size for the upload limit, format for the truth about the file.
- Step 3: If the image is the wrong size, fix it with our Image Resize or Image Compressor tools.
Why Use It
Forms, marketplaces and exam portals all reject images for silent reasons — too many pixels, too many kilobytes, the wrong shape. Thirty seconds here tells you exactly where you stand instead of another failed upload. The tool is free, instant and private.
Frequently Asked Questions
Q: Why does the real format matter?
A: Some sites reject files whose extension lies about the contents. A ‘photo.jpg’ that is really a PNG can fail uploads or print badly — this checker catches that.
Q: What is a megapixel?
A: One million pixels. A 4000 × 3000 photo is 12 megapixels. More megapixels mean more detail and usually a bigger file.
Q: What aspect ratio do I need?
A: 1:1 for profile pictures, 16:9 for video thumbnails and banners, 4:5 or 3:4 for portrait social posts, and the exact ratio most forms state in their instructions.
Tip: If a form gives a maximum in KB and a size in pixels, check both here — meeting one limit does not guarantee the other.