How to resize images for websites and forms
Control pixel dimensions, aspect ratio and file size before uploading.
Pixel dimensions and file size are different
A 4000-pixel photograph can still be heavily compressed, while a 1200-pixel image can be large if saved as PNG. Resizing changes the number of pixels. Compression changes how those pixels are stored. The best results often use both.
Keep the aspect ratio
Locking the aspect ratio prevents faces, documents and logos from stretching. Enter one dimension and allow the other to be calculated automatically. Only unlock the ratio when the destination requires an exact canvas and distortion is acceptable.
Practical width ranges
For many website content images, 1200 to 2000 pixels wide is sufficient. Thumbnails can be much smaller. Document upload portals often accept images around 1500 to 2500 pixels, but the visible text must remain clear.
Do not enlarge small images without a reason
Increasing pixel dimensions cannot recreate detail that was not captured. It can make a file larger while leaving it blurry. Keep the original size or obtain a higher-resolution source when quality is insufficient.
Test the result on the actual destination
Open the resized image at 100% zoom and upload a test file where possible. Confirm that the service accepts the format and that small text, barcodes and identification details remain readable.