WordPress Image Size Lab
Drop an image in. See every copy WordPress will make of it.
Runs in your browser. Nothing is uploaded.
Drop an image here
or click to choose one
Your file is read in your browser and never uploaded. There is no size limit and no daily quota, because there is no server to pay for.
About the WordPress Image Size Lab
Upload an image and see every derivative WordPress will actually generate — thumbnail, medium, large, 1536, 2048, and the -scaled copy — at real dimensions with real crop boxes. Then download the set, or copy the add_image_size() code to change it.
FAQ
Questions
What image sizes does WordPress actually create?
On a stock install, six: thumbnail (150×150, hard-cropped), medium (300×300), medium_large (768w), large (1024×1024), 1536×1536 and 2048×2048. Plus a '-scaled' copy if your image is over 2560px. Every plugin and theme can register more — WooCommerce adds three.
Why is my image blurry after uploading to WordPress?
Almost always the '-scaled' behaviour. Since 5.3, WordPress downscales any upload whose longest edge exceeds 2560px and serves that copy instead of your original. Your original is still on the server; it is simply never used. Drop your image into the tool above and it will tell you whether this is happening to you.
Are the file sizes this tool shows accurate?
The dimensions and crop boxes are exact — they come from the same rules WordPress uses. The file sizes are ESTIMATES: your browser does not use the same JPEG encoder as your server (WordPress uses GD or Imagick and re-encodes at quality 82), so the real files will differ. We would rather tell you that than quietly round in our favour.